Done so often in Hatenkou Yuugi, it could as well be the manga's middle name. Seriously, it can and will happen up to several times in a single chapter; and with such maestria!
Future Diary does this at the end of every episode, after a horrifying or dramatic event, it is then followed by a hilarious segment featuring Mur Mur interacting with several characters. The most notable whiplash is at the end of episode 17, after Yuki discovers his mother died he freaks out, after that, Mur Mur's segment features her having hijinks with Marco and Ai.
The manga Absolute Boyfriend is a gag-manga shoujo-story about a Magical Boyfriend and the protagonist Riiko, including scenes like stuffing cigarettes into smoking ears to avoid suspicion and boyfriends in pocket-size and... questioning a robot's worth and a horribly gut-wrenching Downer Ending.
The anime adaptation of Attack on Titan quickly gained notoriety for being able to use this trope for the fullest impact and dramatic effect. Director Tetsuro Araki managed to create seamless transitions between triumphant victory and hope to multiple character deaths and complete despair for the main characters, as well as vice versa, impeccably well.
Now and Then, Here and There kicks off as a lighthearted show about Shu, a carefree, immature young boy straight out of a shonen anime geared at selling toys. (In fact, the creator later re-used him in Legendz). At the end of the first episode, after tussling with some badguys over a mysterious girl, Shu gets sucked into a bizarre portal and transported to a fantastical far off land of mass drought, child soldiers, child SEX SLAVERY, never-ending warfare, and dead cats. GOTCHA!
Puella Magi Madoka Magica's Episode 3. The first 2 episodes managed to set a fairly dark mood, but still pale in comparison with the end of episode 3.
During the episode itself was a spectacular Mood Whiplash. Halfway into the episode, you have Mami and Madoka sharing their sincerest feelings with each other, both of them feeling inspired after the conversation. Mami dies gruesomely five minutes after.
Fansubbers exclusive, but the "Morning Rescue" commercials in the Madoka Fansubbers tend to serve as this. We get dark, creepy magical girl show mood and suddenly, wacky commercial. Fans quickly latched onto it, seeing it as a refuge from the depressing and horrific nature of the show.
Episode 10 has several impressive moments, such as Madoka excitedly hugging Homura after a successful battle, immediately followed by the disastrous results of Walpurgisnacht's attack: Mami is apparently dead, and Homura watches helplessly as Madoka becomes a witch.
The Fruits Basket manga loves this. After a serious chapter or two, it'll switch to one that's light hearted. Those chapters usually involve the student council.
The anime manages it within a single episode (9) from comedy (Shigure's pranks on his long suffering editor) to loneliness (It is Tohru's first New Year without her mother) and finally friendship (Yuki and Kyo don't let her spend it alone).
Episode 13/the beginning of volume 4 goes from comedic (featuring Black Haru) to dark and unsettling (featuring Yuki and Akito) to heartwarming (with Yuki and Tohru), all in the course of half an episode.
My Neighbor Totoro has this on its own. Satsuki and Mei meeting their fun new next-door neighbors that live in the woods around the shrine, with ten minutes of Satsuki running around town trying to find Mei, who appears to have drowned in the river, before the end (which has more mostly-lighthearted fun).
Elfen Lied has a lot of similar whiplashes, intermixing light-hearted comedy, sweet romance, heart-wrenching drama, and sadistic carnage.
Hell, Elfen Lied even begins with severe whiplash, starting with a mildly vapid secretary-like woman which seems to suggest that the viewer is in for a lighthearted family romp...until she is brutally decapitated by the ACTUAL HEROINE's invisible powers, just because SHE GOT IN THE WAY.
Not to mention the J-pop ED played after said carnage
There's also the intro, especially in the first episode. Elfen Lied's intro, Lillium, can be seen as a calming, soothing, beautiful song, set to imagery that pays tribute to Gustav Klimt's artwork. What's the first thing the viewer sees after the intro? A twitching, bloodied, severed arm. Then the carnage only proceeds to get worse.
Saikano: The mood often switches radically on the same page. Repeatedly.
Many of the later episodes would finish with some amount of horror (Shinji's bloodcurdling scream at the sight of an injured Toji in episode eighteen; Asuka wailing that she "hates everyone" in twenty-two) that would be immediately followed by the light-hearted "Fly Me to the Moon". The ending theme for episode twenty-two is particularly unnerving.
The show is largely a run-of-the-mill Shōnen series up until Episode 18, which was made around the time Hideaki Anno had a massive psychological crisis involving depression that he had to go into therapy for. Episodes after this "epoch" are noticeably darker, bloodier, and sadder than the previous episodes. Mood Whiplash? Ohhhhh yes.
Despite the incredibly depressing content, EVA's theme music is some of the most upbeat around. It almost taunts you, as you know what to expect after it ends.
All of Kodomo no Omocha deals with tears and laughter, usually in the same episode. Most consider it a well-done portrayal of growing up.
Mai-HiME had a humorous beach episode right after a female character's boyfriend disintegrated in her arms, and she went catatonic.
An even more drastic example in the same series is episode sixteen, where literally seconds after the HiMEs are declaring their eternal friendship, the Lovable Traitor Nagi tells them that they must fight each other in an Involuntary Battle to the Death, in which defeat causes the same disintegration to the person dearest to the loser.
The Post Episode Trailers are often humorous, in contrast to the dark tone of later episodes, often making light of the tragic and horrific events that happen in them. In the preview for Episode 25, Yuuichi asks Mai to repeat what she said to him as he was dying from Shiho's Child being destroyed, noting that he couldn't hear her and that he can't ascend to Heaven until he hears it, causing her to refuse to tell him out of annoyance.
Also seen in Jinki:Extend which was one series, but based on a manga and its sequel.
Your Lie in April can swing from happy romantic comedy to tragic and tense drama in mere seconds.
At the end of episode 4, Kaori and Kousei finish their performance to massive applause from the audience... and a few seconds later, we hear Kaori collapsing. This is the start of Kaori's declining health.
In episode 16, Kousei explains to Nagi the kind of person Kaori is, calling her a "strong person". Cue a scene of Kaori crying because she can't hold her violin bow properly anymore. Seconds later, we cut to a scene of the gang visiting Kaori at the hospital, with Kaori's anger at Kousei for not bringing her any gifts entirely Played for Laughs. After Kousei reveals he's giving Nagi piano lessons, Kaori's further enraged because she thinks he's not taking his upcoming competition seriously to the point she starts crying and makes everyone in the room speechless. The next scene has Kousei visiting Kaori alone at night, with her attitude before drawing parallels to his own mother's behavior shortly before her death, further foreshadowing Kaori's eventual demise.
In episode 20, Kousei finally admits to Watari that he's also interested in Kaori, prompting the latter to joke about having competition. Then, when they reach Kaori's hospital room, they see that her condition has taken a sudden turn for the worse.
In episode 22:
After Kashiwagi gives Tsubaki some sage advice, Tsubaki asks how she knows so much. The answer? Yaoi books.
While Kousei is standing in front of some train tracks morosely thinking about Kaori's posthumous words, Tsubaki shows up and kicks him in the shin again.
Legendz: from slapstick, Cartoon Physics and random humor suddenly to horror, Tear Jerkers, suffering and heavy morality. Incredible achievement on behalf of the director and writers.
Naru in Love Hina is a champion (it is the lead in for her Megaton Punch), but Motoko is also well versed in it. Keitaro plummets into anguish with equal speed.
CLANNAD is guilty of this in the second half of the After Story series. To give an example, take the episode where Nagisa died. Heart wrenching, of course, with Tomoya quickly becoming a crying wreck while holding his newly born child Aaaaaaand cue the upbeat happy J-pop ED!
And then that same child dies in his arms 5 years later. Aaaaand cue the upbeat J-pop ED!
The main series is also this. You can spend a whole episode laughing, then switch to crying in the next, and then back to laughing in the following episode, thanks to the show actively switches between high school comedy and heavy drama.
It can also happen in the same episode, especially where Fuuko or Sunohara are involved. This troper has had moments where tears were still running down her cheeks from the previous scene, yet she was laughing at a comical moment.
Lampshaded towards the end of the first season when Tomoya and Nagisa are talking about her part in the play... and how she burst into song at the end of her performance.
Bleach takes this to a whole 'nother level. While it already had standard Mood Whiplash episodes following dramatic episodes (usually revolving around Kon, Ichigo's sisters, or Fake Ultimate Hero Don Kanonji), during the Filler arc a brief clip comic relief snippet, titled Shinigami Cup, was placed after the credits of each episode. The clip displayed various of Bleach's numerous characters doing all sorts of things, from managing their hair in the morning to attending club meetings.
There's also the ending credits song "Happy People" (as upbeat as it sounds) which premiered at the end of what is probably the least appropriate episode possible. The episode ends with Ichigo falling over in a puddle of his own blood after having been stabbed through the chest. "Happy people! Happy people!"
Another example is the bizarre amount of humor in 3-on-1 fights versus Aizen. In the original Soul Society arc, Ichigo and Renji are trying to protect Rukia from Aizen, Gin, and Tousen, and they insert a random laugh moment where Rukia berates Renji for holding his hand over her mouth. The most recent with Isshin, Urahara, and Yoruichi has Urahara and Yoruichi randomly fighting over the quality of Urahara's equipment. Isshin can only stand there annoyed. Aizen even points out that Urahara's silliness in this particular fight is an act.
The battle against Szayel takes the cake. It's about half wacky humour between Ishida, Renji, Pessche and Dondochakka, and half Renji and Ishida getting their organs destroyed. Later when Mayuri turns up to save the day, there is some comic relief between him and Ishida which quickly becomes Fridge Horror when you realize this is the guy who tortured his grandfather to death.
Yumichika and Charlotte's fight starts off looking like pure comedy filler between a narcissist and his Evil Counterpart. Cue Mood Whiplash when Yumichika's secret abilities are suddenly revealed. Fridge Brilliance reveals Charlotte and the 11th division have the same philosophy (direct combat prowess) and that Yumichika's objection is therefore to the 11th division philosophy itself. Fridge Horror reveals this means the so-called narcissist's sacrificing himself for a philosophy he doesn't believe in because his true philosophy is the importance of loyalty.
Fullmetal Alchemist often includes humorous moments in the middle of fights. The author has stated herself that manga is supposed to be entertaining, and thus wanted to minimize the focus on sad scenes (then again, this is the same manga that has Hughes' funeral scene).
The manga has gone so far as to actually throw in a humorous moment right after a character meets a gruesome fate, in the same scene, namely, Yoki charging in right after Heinkel rips Kimbley's throat out, or having characters crack jokes about political propaganda right next to Mrs Bradley breaking down when told her husband and child are apparently dead. In chapter 102 she also throws one in when, Edward comically pulls Roy over by the ankle when he mentions the Gate to check to see if he still has all his limbs TWO PANELS before it's revealed that Roy has lost his eyesight to the Gate. As the series progresses, things get darker and more serious, but instead of cutting the humor, it refuges in more extreme mood whiplashes and Gallows Humor.
In episode 56 of Brotherhood, It has been announced that the forces of good have taken over Central and everyone is cheering, complete with triumphant music, but is quickly turned around with just two words, "I'm back" (Fuhrer Bradley) The forces of good are thoroughly curb-stomped (even a damn tank!!!) .
The 2003 anime version has plenty of Mood Whiplash as well. It'll be serious, serious — ten seconds of comedy that come out of nowhere — back to serious. There seems to be less of this in the latter portion of the series, which could probably be attributed to many things including the darker tone of the show overall and the anime having overtaken the manga. The 2003 anime makes use of detached, non-canonical OVAs for the Mood Whiplash feel. For example, the Chibi Party OVA.
Heck, the first series' first episode is a... quite extreme case of this. It kicks off with a flashback cold open of the brothers trying to ressurect their dead mother, which, as you know, goes to hell pretty quickly, as the exciting scene turns to sheer horror when the audience sees Edward knelt over, clutching a bloody stump where his leg once was, and staring in horror at the... thing he and Al made and then screaming in terror. This is promptly followed by a amusing scene a 15-year old Edward wandering in the desert. note Yeah, that was the start of the first episode.
In Inuyasha this is done routinely as Kagome balances fighting demons and going to school. Several episodes open with Kagome at school fretting about her grades, only to cut to the Big Bad plotting to kill her in his dark castle. One weirdly funny moment occurs when Inuyasha's group is trying to solve a situation where two brothers are trying to kill each other and they're destroying all the villages around in their tussel. Inuyasha rants about the thoughtlessness of brothers warring with each other before realising his friends are staring incredulously. Inuyasha then argues with them about whether or not he's being hypocritical because of his feud with his own brother. Sango randomly wonders whether Sesshoumaru's sneezing as a result of people talking behind his back and the scene does a Sneeze Cut... to Jaken sneezing on Sesshoumaru's behalf. Comedy moment over, it returns to the very serious situation of the two feuding brothers that Inuyasha's group is trying to stop.
Hunter × Hunter is highly fond of this trope. During the beginning, we are treated to a peaceful setting in a Hunter exam where everyone has to be at their prime to qualify the next round. The real kicker begins when a participant, Hisoka, shows his bloodthirsty nature, and kills off a participant for crossing his path. It quickly becomes an Anyone Can Die exam as the unimportant characters get killed left and right.
Moreover, the Mafia Auction in the Yorknew City Arc had the auction begin in a secure and well meaning tone, with Kurapika's several friends and associates. Along with several over the top bets and all. Then the Phantom Troupe showed up.
The real example of this trope comes at the beginning of the Chimera Ant Saga. Gon, Kite, Killua make their way to the castle, to stop the Queen from having birth to the King, while defeating several captains and their mooks. They go on chatting happlily about Ging (Kite's mentor and Gon's father) along with their superb progress and awesome teamwork under Kite. Then, Neferpitou spots them, teleports to the trio's location and cuts off Kite's right arm before ANYONE has a chance to even react tot his change. Gon prepares to fight off and Killua stops him by knocking him out, getting them to flee. We see the aftermath of the battle as Pitou kills Kite and observes his head.
Even more tragically, when Gon and Killua prepare themselves to get stronger to return to the country and save Kite, complete withtheir triumphant theme song playing in the background. Why is it tragic? They don't know Kite's long dead from the attack. Even the next panel shows Kite's body frozen up as Pitou express her glee that she fought a good opponent.
But what adds to this anime's bipolarity? Remember that infamous scene in Bambi when Bambi finds out his mother is dead and the next scene that follows is happy springtime? Brigadoon ends ALL of its episodes like that! Regardless of happy conclusions or a shocking Cliffhanger at the end of each episode, the series ends each episode with a sugary-sweet ED.
An in-episode example would be "Speak Like a Child." Most of the episode is lighthearted and silly as Spike and Jet attempt to find the right equipment to watch a mysterious videotape. When they finally succeed, they find out that the tape is a message which Faye made as a child and sent to herself in the future, telling her never to lose her younger self. She doesn't remember a thing.
Used quite well in "Waltz for Venus". Towards the end of the episode, Spike and Roco, who Spike met in that episode, confront a gang that Roco stole a valuable plant from (to cure his sick sister). As the fight starts, it plays typical, upbeat fight music. Eventually a gang member comes after Roco, but he quickly defeats him by using a technique that Spike had tried to teach him earlier in the episode. He is so happy that he did the technique right that he gives Spike a thumbs up. Spike returns the thumbs up and immediately after, Roco is shot and the music stops. The Mood Whiplash makes Roco's death hit the viewer pretty hard, even though he was only introduced that episode.
And in contrast to the last two examples, the finale of "Ballad of Fallen Angels," the first of the Heroic Bloodshed episodes which featured Spike's first epic throwdown with his enemy Vicious. We're treated to a beautiful flashback of Spike and Julia, where Spike says to her, "Just like that...sing for me, please." And then we return to the present where Spike wakes up, all wrapped up in bandages due to all the crap he got put through during that fight, and Faye is singing quietly. Spike calls Faye over, motioning for her to lean close, and then..."You sing off key." And Faye goes into instant tsuntsun mode and lets him have it, ending the episode on a hilarious note.
Excel Saga, while mostly a parodic anime, does this later in the series, having moving moments almost directly followed by comedy. The biggest shock is when Il Palazzo shoots Excel at the end of episode 23, even though he did the same thing at the beginning of episode 1 as well as numerous other times throughout the series, and Excel dies so often that you lose count.
The "Kiss Kiss Carnival" chapters being immediately followed by a series of Wham Chapters.
Chapter 304 of the Manga pulls this off with a great back-and-forth; when Negima prepares to start a big, climactic fight with the mysterious villain Dynamis, Dynamis announces he's going into his strongest form.... which involves him getting naked. Just as Negi's Nakama are recovering from the shock (some of them rather pleased) it goes back to serious when Dynamis starts beating the crap out of Negi and the previously-disposed of Five-Bad Band come back to fight some more. But then Ako announces she can give the group the strength buff they need to overcome the odds and beat their enemies.... by sticking a giant, magical needle in their butts.
Chapter 340 wields this trope like a blunt weapon. Asuna's back, and saved Negi: Awesome. Then they start hugging. Then they get into one of their usual arguments, with what is essentially God standing RIGHT THERE: Funny. Then Asuna and Negi defeat the Big Bad, and it turns out God hijacked Nagi's body at some point and the only thing he could say after seeing his son for the first time in Six years? "Negi, come and kill me. Then everything will be over." OH look, here comes the tears.
Tengen Toppa Gurren Lagann - slams very rapidly from sad to inspirational to very, very sad when Kamina is mortally wounded, but gets back up and destroys the remaining opposition in a stirring scene... then he dies. Later, during the first few post-Time Skip episodes, after a fast-paced rollercoaster ride of over-the-top badassitude, it seems like the show actually jumped off the same slippery slope that took Neon Genesis Evangelion. Fortunately, that was just to build up momentum to fly up even further Up to Eleven.
In Lagann-hen,this goes in reverse; when the Cathedral Lazengann has been activated and is about to punch out the Earth, things look bad and the mood is relatively dramatic... then Lordgenome hacksthe Cathedral, in what is considered one of the funniest scenes in the movie.
If you're watching Gurren Lagann on the Sci-Fi channel, you get an additional whiplash if you stick around after the show's end to see... Now and Then, Here and There. Talk about mood whiplash!
Gravitation regularly flip-flops between comedy and angst, depending on how Shuichi reacts to the events happening to him. The most extreme example was after a slapstick sequence of Shuichi and Aizawa being chased by fangirls, then getting drunk together, when three other men hired by Aizawa come in, and they beat and rape Shuichi.
Schoolgirl cosplay directly post brutal assault, anyone?
How about the end of the anime when Eiri's suicide attempt is interrupted by Shuichi bursting through the ceiling in a dog costume.
Zeta Gundam, the darkest entry in the Mobile Suit Gundam saga, was followed up by Gundam ZZ, a comedic hijinks series. Following negative reactions, ZZ shifted gears halfway through its run, focusing on drama and politics.
To be fair, Tomino had a history of following up epic tragedies with comedies, and depressions caused by Executive Meddling can be attributed to at least a few of his Kill 'em All endings anyways.
Speaking of Gundam, the ongoing story arcs from the parody manga Kidou Senshi Gundam San are the absolute king of this. Best example would probably be Garma of the Space Island, a goofy Slice of Life story about the Zabi clan as a poor family living in a Japanese-style shack. Things take a turn for the worse after Zeon Deikun shows up, but the absolute biggest Wham Episode comes when it turns out the whole thing was Kycilia reminiscing about her dead family, right when Char shows up to deliver her memorable death scene.
Gundam Build Fighters has a little of this as well, welding comic relief scenes with scenes of intense fights and slight drama. The worst of this has to be in episode 20 which in one scene, in order to recall a past memory, Sei ends up quoting all 43 episodes of the original Mobile Suit Gundam to a scene where Aila is forced to fight, and when she refuses, is suffered through Mind Rape. She ends up not only decimating a recurring character's Gunpla but get unfairly get called out on when Reiji, a boy she loves, hatefully yells at her. Fortunately, this series comes back to the lighter side in Episode 21 when she and Reiji reconcile.
Episode 21 itself piles on the feels, with Reiji's hate and Aila's despair, then heartwarming as they reconcile. Not long afterwards, Reiji and Aila get into a shouting match over who's going to win before Aila quits Team Nemesis and calls out Nine Barthess, Josef Kankaansyrjä and his grandson. After all of that, the rest of the match shows them flirting while beating each other up. It's as simultaneously heartwarming, humorous, and awesome as you might expect.
Higurashi generally starts each arc with someone dying horribly (or at least a mutilated corpse in plain sight). And then on the other side of the opening credits, lighthearted comedy. And then things go steadily downhill again.
The first season's ending theme provides this effect, especially with the ending of Meakashi-hen:After an episode of bloody carnage, the last shot we see is of Shion falling to her death, so taking Watanagashi-hen into account, the entire cast of main characters save for Rena and Oishi are now dead. The screen goes black, and we hear the splat of her body hitting the ground. Cut to the ending credits to a light, soothing piano piece.
There's probably at least one person who tuned in to the first episode right after the first scene and opening credits, knowing nothing about the show, and assumed the series was a comedy. It must be like playing Eversion blind.
The anime has two noticeable whip lashes. Right after Meakashi ends, the arc where Shion goes the murder spree that ruined her reputation, we see her again in the next episode. Normal and happy, back to her Genki Girl self; it's more striking than with the other characters. Next is at the end of the first season. Everything seems happy and fine, until you notice this is another world, which is why everyone's happy and back to normal.
The whole series is an expert in Mood Whiplash as it often turns a funny or cute scene into a surprising or even nightmare bringing scene. What is creepy in the anime is often scary or terrifying in the manga where you sometimes almost don't dare to turn to the next page. Like in Onikakushi-hen chapter 3 (in where there are no less than 4 changes in mood in just a few pages) when Keiichi confronts Rena about her and Mion keeping secrets from him only for Rena to turn the tables on him and instead accuse him of keeping secrets from his friends. It's all seems to be end peacefully when Rena calms down, until you turn the page and see this, complete in colour and all. It is without warning and you have to read carefully to even notice that the page before was also in colour. And now imagine a series full of similar things...
One notable scene in the manga is Shion's death. We see her falling, then are shown a very cute scene of "What if" she had been friends with the others that's very much like what happens in the Kai arcs, before we get a gory shot of her dead body.
The manga is bad about this, often using omakes at the end or beginning of a chapter. It's especially noticeable at the end of Minagoroshi. Right after a Downer Ending there are a bunch of omakes making fun of the depressing scenes, and lampshading Miyo's odd facial expressions.
The Prince of Tennis does this so violently (and very, very deliberately) that if you aren't ready for the Mood Whiplash between high-stakes tournament finales and alternate universe chibi adventures, you're liable to end up in a neck brace.
Done near the end of Lucky Star, when the normal sequence of slice-of-life gags is broken by a touching segment on why Konata's late mother chose her father.
YuYu Hakusho does this occasionally, interspersing their tense battles with weird and unexpected humor, such as when Kuwabara is about to die in his fight with Risho, and Yukina's appearance suddenly makes him super strong; he knocks Risho out with one blow and then proceeds to do muscle-man poses to impress her. Another one of note was when Chuu, in the middle of the power-up which will herald his ultimate technique, runs to the edge of the ring and starts throwing up.
Slayers adores this and makes full use of it, including hanging lampshades on it at every opportunity. In a particularly memorable scene, Lina has been put out of action and is possibly dead despite Sylphiel's efforts, the rest of the cast are facing the season's Big Bad with various injuries and no hope of winning — and Amelia's overprotective father, the ridiculously over-the-top Prince Philionel, arrives from nowhere and makes a fool out of himself by challenging the enemy in the name of justice. Zelgadis explains this by commenting, "Well, they can't let these episodes get too serious."
Arguably the entire point of the weird broadcast order of episodes is to recreate the mood whiplash that occurs in the novels, but on a 12-Episode Anime timescale. More directly, though, the Wham Episode probably qualifies as mood whiplash, as a series about the personal weirdness of its title character suddenly turns out to be about the very real dangers that puts the rest of the cast into.
In the Wham Episode, Haruhi is ridiculously bored, and braids Mikuru's hair. Can't fault Mikuru for shivering in fear at what Haruhi might do to her. For the record, Haruhi used Mikuru to blackmail the Computer Club President on charges of sexual harassment, and forcefully stripped her several times, though not at the same time. Kyon goes home and soon sleeps. When he wakes up, it turns out they're in a separate universe, created by Haruhi herself, and they don't know how to get out.
Asakura's big scene previously would also count. It's set up to look like a fourth fraction declaration(and love confession parody). And the series is shaping up to a be comedy/drama at this point. Then suddenly you get this line without warning or a change in tone of voice: Asakura: "That's why I'm going to kill you and see how Miss Suzumiya reacts." She pulls out a knife and makes with the stabbing. This is followed by reality-warping KUNG-FU action! It's still the only real action scene in the anime and one of only 2 in the Light Novels.
The 8th volume of D.Gray-Man features this trope in a particularly jarring way. After the last page, when everyone on the ship dies cheering on the main characters after Miranda deactivates her innocence, from the woman and her bodyguard that were set up to be main (or at least recurring) characters to the nameless crewmen celebrating for the last time belowdecks, the very next page is an omake featuring the wacky hijinks of the creator and her assistants.
Chapter 189 begins with someone surveying the carnage left after an attack by the Noah, then cuts to the fact that Allen just dropped out of the Ark straight onto the Earl's head. The goofiness then gives way to the Fourteenth being freaky as hell, and Allen starts thrashing around, clutching his head and screaming "No, no!"- then he headbutts the Earl across the room. It also features Kanda freaking out about his hair tie again. The sudden attack of silliness is really, really jarring, considering the lack of comedy in the preceding few installments and the fact that it seems like the weirdest possible place to put it.
Also in the anime, when everyone thinks Allen is dead and learn they can't even see him, after spending the last few episodes on some pretty heavy life and death stuff, suddenly Miranda appears and trips down the deck of the ship. Then again when it seems that Kanda's just died, next comes extended comedic scenes on the debt which Allen's master wracked up and what he made two of the Noahs do as they tried to find him. Very funny, but also very sudden given the extremely serious nature of the episodes before it.
Tsukuyomi Moonphase flips from the light-hearted, daily life of a cute monster girl and her surrogate family, to dark, full-out battle sequences between the villains that almost look like they're from another show! The main title sequence doesn't help any.
Jubei-chan uses this to great effect. One moment Jiyu's engaged in some heartwarming highjinks, the next she's plummeting down a cliff face with high velocity blood loss.
Violinist of Hameln is the king of this trope. Accept no substitutes. The series flips from drama, tragedy, and angst to heartwarming romance and then to outright ludicrous gags pretty much with the turning of a page; to list every instance of Mood Whiplash would be to summarize every page and line of dialogue. The real kicker is that it's pulled off surprisingly well and the characters become very complex as a result. Note that this only applies to the manga, the Anime starts out horribly sad and pretty much stays that way.
Rozen Maiden much? The series mixes the daily antics of a group of immature, childish dolls trying to acclimate themselves to and enjoy their new life, with much hilarity ensuing...except that these same dolls are forced to compete in a Highlander-style fight, forced to kill their own sisters or be killed by them.
Kanon keeps bouncing between sad, comedic, and heartwarming.
Honey and Clover is a series that handles the whiplash from madcap comedy to rather dramatic introspection, then to near melodramatic romance quite well throughout the entire run, and even within the same episode.
Gintama has a fair share of serious moments, but is still a Gag Series, and as such, has a habit of shifting back to being hilarious in the blink of an eye.
SoltyRei has some episodes where the transition between comedy and serious, somewhat-noirish action takes place in a matter of seconds.
Strike Witches is, for the first eight episodes, a light fanservice show with regular Neuroi attacks, albeit with reference to the war going on in the background. The end of episode eight shows the titular unit's commander pointing a gun at her second in command, demanding her resignation. Things get even worse from then on, up to and including a conspiracy to pull the Witches out of battle.
Busou Renkin starts with the main character getting stabbed right though the chest to the main character waking up and causing a mess in the dorms screaming that he was killed and that he will be avenged. The series flip-flops between the hilarious and the deathly serious fairly consistently.
Code Geass often had this, either ending comic episodes on a jarring twist or following a Breather Episode with a tragic Wham Episode. A fairly low key example early in the series was a humorous episode about trying to catch a stray cat that got Zero's mask stuck on its head, which ended with the Emperor delivering an unsettling Social Darwinist speech broadcast on every television in Britannia, talking about how evil equality is. The kicker was in the second season where the very last comic episode focuses on Milly's graduation celebration, where boys wear blue hats and girls wear pink hats, and if someone steals someone else's hat and puts it on, those two have to become boyfriend/girlfriend. There had been a Will They or Won't They? looming over Shirley and Lelouch for the entire series until that point, when Lelouch essentially handed his hat over to Shirley, showing that he was finally willing to return her feelings. The episode ended with Shirley regaining her memories, causing her to become aware of Japan's and Britannia's Gambit Pileup (and remember that she had tried to murder Lelouch after he killed her father the previous year), leaving her with literally nobody to trust. It goes From Bad to Worse.
Trigun marks the end of its comedic side with the introduction of Legato.
A more straight-up case of whiplash comes in episode six, where after a series of largely comedic episodes, the mood shifts gears and actually shows the audience the consequences of Vash (somehow) having destroyed a city without killing anyone inside.
Another example is when Wolfwood dies. The next episode starts just like the earlier onees with Vash doing some zany antics and eating donuts, giving us some hope that maybe what we saw last time wasn't absolute. Then in the middle of a "Donuts are awesome!" funny scene, Vash starts to cry, driving it home that yes, Wolfwood actually died. Oh, and this is also the episode when Vash kills Legato and goes into a Heroic B.S.O.D. about having to kill someone, so it just keeps getting worse.
Alice Academy jumps from a light hearted ten year old school girl life to Someone is going to die in five second if you don't do something, someone is missing and probably dead, someone is kidnapped and so on.
Full Metal Panic! did this in the first season, alternating between wacky high school hijinks and Real Robot action arcs that could get rather grim. The sequels compartmentalised the two halves with all comedic Full Metal Panic? Fumoffu and more action/drama oriented The Second Raid having far few comedic moments though it wasn't entirely devoid of them, partly thanks to Gates.
At first glance, The Noozles seems like an innocent, light-hearted anime about talking koala bears — until you get to its surprisingly deep Myth Arc and its apocalyptic, horrific final episode.
Axis Powers Hetalia is usually a cute and silly series, but occasional has strips that are very serious and sad (such as Russia's History and America Cleans the Storage). Interestingly, in a Japanese poll for the first volume, one of these serious strips ranked first.
If you follow the anime- episode 45. The previous episode was the usual comedy (with Swirzerland trying to teach self defense to Liechtenstein, Canada's Butt-Monkey episode an some cute America and Japan stuff), and then, bam!, you get a flashback (of Liechtenstein almost Dying Alone in the rain after World War I pushes her close to the Despair Event Horizon) that is far more dramatic than it was in the manga at the start and by the end, Liech is saved by Switzerland, and then in the present, she thanks him) in an episode that is basically completely serious, though not dark.
Between the sad parts of America cleans out the storage you have the episode with Rome's song andthe episode with Italy trying to spy on the Allies. Basically you have light hearted episode 15 with Japan and Western Cultures, more serious episode 16 about China's and Japan's history, episode 17 which is about America remembering about his and England's past, episode 18 with Rome's song, episode 19 with Canada not being noticed then back to sad for the continuation of America's Cleaning Out the Storage.
The "While you were gone" comic strips seem like lighthearted fluff, with Italy and Poland pranking Lithuania, until Po walks in on him in the bath and sees his scars.
"So there's a side of Lithuania...I don't know..."
Many strips that feature Lithuania seems to devolve into Mood Whiplash, even if he is not the direct recipient given his presence in the aforementioned Cleaning out the Storage and Bloody Sunday strips in addition to those dealing with his own history.
Tsubasa -RESERVoir CHRoNiCLE- could be considered an example of this. Most of the first half of the series contained a light-hearted, action-y atmosphere, like what you'd generally expect from some Shounen manga. However, it takes a left turn when the original Syaoran wakes up, and "Syaoran" is revealed to be a clone that suddenly falls into a trance-like state, in which he also takes Fai's eye for his own, and leaves the group. The anime adaptation chose to substitute later story arcs with filler episodes that maintained the lighthearted nature of the beginning of the manga; later, a different animation company produced two OVAs chronicling some of the darker story arcs of the manga.
In Ghost Hunt most episodes are strait-forward paranormal research/horror, except for those bits of romantic comedy that seem to pop out of nowhere.
Shakugan no Shana. The series tends to shift between a dark, supernatural action show, to a Moe school-yard romantic comedy.
Zombie Loan. The manga more so than the anime, but in both cases, the series gravitates between slapstick and character-driven comedy to scenes of extreme violence and gore.
The manga has the title character coming back to the village from a particularly arduous battle to find the entire village congratulating him and recognizing him as a hero. This is then followed by a rather amusing scene of a squad of Cloud nin coming the village to inform them their village plans to take care of Sasuke and Akatsuki while one of them talks about theoretical girlfriends he would get while traveling but upset when he leaves them. But thenwe find out that Tsunade's attempt to save the villager's from Pain's attack didn't just render her unconscious, but put her in a coma so the village council decides she needs to be replaced in the meantime and Danzo successfully pushes his way into the becoming the acting Sixth Hokage. All of this in one chapter (which is called "The Joyful Village").
Ranma ˝ has at least one moment of this. For most of the series, threats of death and massive destruction have been thrown around and treated comedically. Even though some characters have tried killing their enemies, they have never succeeded, and nobody seems to mind when the main characters level a house or smash through a wall. Then, we get the Ryuu Kumon story arc, where we get to see as a young boy is orphaned when his house collapses on his father, explicitly crushing him to death and leaving him with nothing but the clothes on his back, his father's last words, and a scroll of martial arts techniques. Another mood whiplash, or a reaction of a different sort, may result when you realise the fact that the cause of the tragedy was stupidity of a Darwin Awards level. Seriously, what kind of idiot practices a move explicitly stated as a back-breaking bearhug on the central support pillar that happens to be the sole thing keeping the building from falling down on top of them?
Downplayed in episode seven of the first season since there was a commercial break in between, but we go from a somewhat lighthearted scene of the Arthra crew about to arrive on Earth to Fate being whipped to near unconsciousness by her Abusive Mother.
Episode six of A's has seven and a half minutes of near nonstop heartwarming and funny moments with Hayate and the Wolkenritter becoming a family followed immediately by the reveal that Hayate is slowly dying, forcing the Wolkenritter to betray her trust in a desperate bid to save her.
Two chapters in, and Magical Record Lyrical Nanoha Force is already using this. We open with the happy, fun travels of protagonists Tohma and Lily, and after the sequence ends with a cheerful Puni Plush panel of the two, we cut to another planet... where Enforcer Teana is investigating a devastated village while the TSAB unit accompanying her assesses the damage and lays out rows and rows of the dead. As Teana questions the heavily injured survivors, it is then implied that Tohma and Lily were the ones responsible for this incident.
Episode 21 of Digimon Adventure 02 sees the defeat of Ken Ichijouji, the Digimon Kaiser. He then breaks down emotionally, realizing he was actually harming living creatures and not playing a realistic video game like he thought he was and that the role of the Kaiser was created to escape his own sadness of losing his brother. To top it off, the poor guy has to watch his Digimon Wormmon die, who, despite Ken's cruelty, displayed nothing but Undying Loyalty to him. Less than a minute later, hijinks ensue when Yamato is chased by Daisuke's sister Jun.
The train scene in episode 41 of Tamers is probably the most extreme example of this trope in the entire franchise. It goes from funny (Takato facing the troubles of having Guilimon on the train and tripping over his feelings about Jeri), to sad (Takato reduced to tears by Jeri's lifeless state), to creepy (Jeri, actually the D-Reaper's agent, reading the ingredients off the back of an energy bar in a cold monotone) all in one scene.
Darker Than Black pulls off a pretty hardcore case of whiplash by accident in episode 6. The episode features a Broken Bird Woobie girl who wants nothing more than to stop killing, and live a happy life by herself. Of course, any Genre Savvy viewer knows that she dies tragically by the end of the episode. Which she does, courtesy of several large ice spears through the lungs, followed by the sad 'dying in the rain' scene. Quiet/Sad ending theme. Then the preview for the next episode is presented by a hyper-active Moe character with pink hair.
The second season of Black Lagoon has the wisecracky Greenback Jane storyline sandwiched between the (tragically horrific) Vampire Twins and (horrifically tragic) Fujiyama Gangster Paradise storylines.
The Black Butler ending themes. The first half has I'm ALIVE! which is an upbeat song that's accompanied by adorable, brightly colored animations of chibi versions of all the characters. The second ending, Lacrimosa (which means "Tearful" or "Mourning" in Latin), has a much sadder tone and the animation features a regular Sebastian rowing a boat along a river with Ciel laying in a bed of white flowers; the colors of the whole image are rather muted, too.
This happens in the manga, too; one chapter featured The Heroordering his butler to burn down a building full of hostages. The next chapter has an eccentric tailor come to fit him with some new clothes and running-around-half-naked hijinksensue.
In the manga, after the long, intense and revealing Campagnia story arc, the next chapter is an Easter Egg hunt with all the typical, hilarious hijinks and comedy one would expect from the earlier chapters.
If you want to talk about Kuro, please see the very first five minutes of the very first episode of the second season. This episode introduces Alois Trancy, who, in the first minute of the episode is sitting on a bed, covered in bruises next to a much older man, while he repeats the word 'darkness' over and over again. Then he suddenly switches from his solemn state and yells "I WANT THIS! I WANT YOU!". Then, after the theme song, the kid switches from Ax-Crazy to adorable and quirky to melancholic to incredibly flamboyant so much that your neck will be broken by the time the eyecatch plays.
Kei: Even if I scream and beg, the results are the same.
Parodied in Ninin Ga Shinobuden. The series is more or less entirely comic, but the ending of episode six is treated entirely dramatically, complete with hints at a dramatic backstory and overarcing plot line. The rest of the series completely ignores this scene until the last episode, when the characters realize that they forgot to follow up on that plot thread, and attempt to create a Magical Girl storyline as a cover.
Sgt. Frog veers into this whenever it goes into its more serious arcs. Even when an installment is played for mostly seriousness, jokes are still spattered throughout... and naturally such chapters are bookended by lighthearted comedy chapters. A tad jarring when Zoruru's return and deadly duel with Dororo in Volume 17 is filled with lighthearted jokes at their expense and startling half-reveals about their history...
The Fairy Tail anime overlays the beginning of the upbeat, cheery, teeth-meltingly sweet ending theme over the final scene in the episode. Regardless of what that scene might be. Comedy often results. This is one of the series's main sources of humor; even during some of the most dramatic moments of the series, some humorous occurrence may occur when least expected.
In the Fighting Festival Arc, the arc begins with a light hearted peagant competition for ladies of Fairy Tail guild. Then Evergreen appears and freezes the participants to stone. It then gets worse for the guild as they are forced to fight each other to save the said ladies.
The end of Tenrou Island Arc. The guild just completely defeated Grimoire heart, and saving the exam in process, as well as a possible redemption quest opened for Hades. Fairy Tail parties as they always do in the end, and Cana is reunited with Gildarts. Then, Zeref gatecrashes Grimoire Heart's airship, freezes Rustyrose and Kain Hikaru in a flash, reveals he was not weak at all, and reminds us why he is called the Ultimate Big Bad, by killing Hades (his heart was repaired at that time). He announces that Fairy Tail is doomed, as Acnologia was on to them now. Few panels later, Fairy Tail gets to experience a dragon's wrathUp to Eleven even with four dragonslayers giving their all (Damn, their entire guild, their STRONGEST part of the guild), all ended up running. They still ended up getting nuked by Acnologia, the said dragon above. They get better thankfully, but that took 7 WHOLE YEARS!! All this in space of 4 chapters.
Ghost Sweeper Mikami refuses to let go of its original comic qualities, even when Cerebus Syndrome manifests. As a result, even individual reports can shift between serious/tense/somber and comedic multiple times.
A number of Hentai series will have light-hearted fanservice in one scene and girls getting raped to death or psychological broken by evil men, demons or unholy cthulhoid abominations in the next, or vice-versa.
Foxy Nudes/Hana no Joshi Ana: Newscaster Etsuko is a two part Hentai OVA focusing on a sexy news anchorwoman who (predictably) uses sex to get top ratings. She goes on scene to a hostage situation, promising to save the hostage...and then flips around and starts staging the entire situation. While for the most part it's a light-hearted sex comedy, the majority of the sex comes from Etsuko herself forcing the drunk kidnapper to repeatedly rape his hostage...and while the other characters have cartoonish reactions to it, the girl herself is repeatedly screaming and crying the entire time...and then towards the end, Etsuko gives the kidnapper a gun (telling him it was a prop), but when it turns out to be real, he fires it at the police, and when a sniper fires back, he accidentally hits...the hostage. And, again, it's treated as a joke, mostly. And to sum up the ending, the kidnapper goes to jail, the sniper gets fired and becomes a sexual masseuse, and Etsuko enjoys high ratings, riches, and sex with her camera man.
And if you're wondering whether or not the girl died, it's never directly said. Every time someone brings it up, it gets laughed off or the topic changes, as if she was a spoiled princess (despite it never being shown or hinted at that) and not a girl who gets repeatedly raped and then shot. It really is quite disturbing if you don't run with the whole Rape as Comedy thing.
Akumetsu intersperses serious violence and talk with cuts to the cute chibi mascot Ametsu-kun.
In the first episode of Brigadoon: Marin and Melan, a killer robot is targeting a little middle school girl. Now, this sounds like a serious situation, but this whole scene is played out like an elaborate Elmer Fudd vs Bugs Bunny chase. While the series does maintain some level of comedy from there on out, this first episode does very little to prepare the viewer for the very serious and sometimes tragic storyline that follows.
Osamu Tezuka did this all the time. Whether it was random insertion of himself into the procedings, an inappropriate appearance by Hyoutan-Tsugi (aka "Gourdski"), a bit of over the top anachronism, or just some plain slapstick, you could rely on Tezuka to insert a bit of humour in all but his most serious stories. To quote a review of Buddha:
"In Tezuka's world, the exquisite collapses into the goofy in a New York minute, the goofy into the melodramatic, the melodramatic into the brutal, and the brutal into the sincerely touching. The surprising result is a work wholly unique and downright fun."
The first episode of Kimba the White Lion also counts. It literally goes from tragedy to comedy and back every minute or so.
On the opposite end of the spectrum, Tezuka was not above killing people in his Astro Boy stories. His trademark cutesy style just makes it worse.
Witchblade, episode 13. Masane has to essentially break Rihoko's heart, and her own by forcing Riho to leave. It ends with a new and bouncy end theme, featuring a group shot of smiling cast members.
Special A's extremely perky second ending theme causes a lot of this - the first one is more restrained and so dramatic ending notes are left be, but the second is just so insanely cheerful it can really throw you for a loop on darker episodes.
This Ugly Yet Beautiful World: What self-advertises as a Fanservice series of light-hearted and silly stories turns shockingly serious by episode 8.
Happens several times in Nadia: The Secret of Blue Water. The most notable example would probably be episode 13, where a cartoony chase scene suddenly turns into an actual matter of life and death when the bad guy gets out of his wacky robot and pulls a gun. To Nadia's horror, Captain Nemo simply shoots him dead. After a tense silence, we cut to the ending credits.
The CP9/Water 7 arc of One Piece practically set this as the main tone of the series. In a matter of roughly five or six episode, Usopp goes from a serious fighter, going head-to-head with Luffy in one of THE most emotional battles in shounen, returns as Sogeking. With a Sogeking theme song.
The CP9 personify this. Great swordsman and second most powerful person on the squad Kaku has giraffe inspired super powers. Mind-raper and corrupt government official Spandam spills coffee over himself and has an elephant sword. And oh-ho-ho, let's not forget the Buster Call. A military operation capable of clearing an island off the entire world is accidentally triggered by Spandam when trying to talk to someone over a similar-looking telephone to the one that initiates the Call. He destroys an entire island and brings up horrible memories to his captive because he is so incompetent.
The tenth movie Strong World is filled to the brim with Mood Whiplash, from Funny to Awesome to Tear Jerker to Heartwarming to Despair, and criss crossing between them all. It has to be seen to be believed.
The Sixth movie should be called "Mood Whiplash The Movie". It starts as a trip to a festival island with funny residents and games such as Goldfish Catching, Ring Toss, and the Shooting Gallery. Halfway through it devolves into a mix of mystery and horror.
The last few chapters of the Sabaody Archipelago Arc. The ending begins with one of the most awesome Enemy Mine by the 3 pirate captains (Luffy, Law, Kidd), defeating all fodder and making their way out as an Admiral arrived on the island. We are treated with the Pirate King's history with his First Mate, and a declaration of oath. Few panels later, said Admiral arrives on the island with 5 Pacifistas, who beat the shit out of many Supernovas within several minutes. To continue, after the stomping, the Army moves on to intercept the Straw Hats. The Straw Hats, who beat every major boss ever whoever came across them. gave their all to defeat 1 Pacifista, not to mention totally wrecked and devastated. Moments later, The Admiral and 2 more Pacifistas arrive, which made the damn Straw Hats try to flee, ultimately failing, and having the crew on verge of extinction. Then Kuma arrives, AND DESTROYS THE STRAW HATS HIMSELF!!! Luffy finally crosses the Despair Event Horizon after he sees his crew vanish with him unable to save them, not even noticing when he was transported. No wonder, Sabaody Archipelago is considered one of the severe arcs in One Piece, barring CP 9 Saga itself!!
Episode 420 of the anime. For the most part, the episode focused on Robin's arrival to Tequila Wolf and her story runs on Rule of Drama, then suddenly at the end, the rest of the episode focused on Usopp's arrival to Boin Archipelago... and it's hilarious, full of slapstick comedy.
Chapter 623: After who knows how long, the little slave girl Koala is finally reunited with her family. The entire village is overjoyed to see her again, and Koala waves Tiger goodbye with both of them smiling widely... then Tiger is ambushed by the Marines, who reveal that Koala's hometown had sold Tiger's location to them in exchange for Koala's safety, and mortally wounded. Worse still is that she wasn't even aware of it.
Chapter 784: Gear Fourth is an example both in and out of universe, due to a huge dissonance between appearance and power. It looks completely ridiculous, even by Luffy standards, like a cross between a particularly musclebound hot air balloon, a parodic Top-Heavy Guy and Luffy himself, and Doffy laughs out loud at his transformation. A couple seconds later, he's wondering why exactly he's in the middle of town, when the actual fight had been happening outside it. Later, the citizens get to see a spectacular dropkick which leaves them awed, which is quickly lost when they see Luffy bouncing around like an actual balloon afterwards. It somehow seems fitting for Luffy to get a form so simultaneously silly and destructive.
My Lovely Ghost Kana dashes suddenly between Genki GirlGenki GirlMagical Girlfriend, a beautiful love story and sad, heartwarming, tragic or even dark]] segments. For example, Kana is floating along, experiencing the world and wondering if there is anything she can do as a sort of "job" when she sees father walking with his young son, who is carrying a box. The boy is talking to the box, telling what is apparently a puppy inside that he is "going home" with the pair. Kana thinks how nice, then the ghost of the dead puppy floats out of the box, licks the boy on the face, and fades away.
Don't forget Ai-Ren: after the day where everyone goes to the beach, Ai peacefully dies in her sleep. Author Tanaka Yutaka is patron saint of this trope.
Pokémon: The First Movie: Before the movie proper, viewers were treated with a happy little short about the heroes' Pokémon having a vacation in a park. Five minutes after it ends, the actual movie then shows a Pokémon killing a bunch of scientists and blowing up the lab it was made in.
An episode of Best Wishes! features a story about Team Rocket infiltrating Colress's base and Meowth being brainwashed into attacking his comrades, intercut with N's investigations into the destruction of a laboratory, and Ash and co. trying to get a seed stuck out of Pignite's nose.
Played far more seriously in a first-season episode in which Misty leaves her Psyduck at a daycare that emphasizes The Power of Love, only to go back for it while complaining that the one time she needs it for something (which is relatively trivial) is the one time she leaves it someplace. She and the others sneak in to discover that all the Pokémon are locked in small cages and about to be shipped off to the boss of Team Rocket.
Sun and Moon had a double feature episode set. The first episode had Ash and Pikachu having an adventure where they meet another one of the Tapus. The next episode has the apparent death of Litten's Stoutland mentor.
The Nebby arc gets Darker and Edgier when Nihilego is brought into the picture as the source of two incidents involving Lillie and her family.
Galaxy Angel, usually utterly silly, and a parody of serious anime in general, will throw in a sad, heartfelt, or action-oriented episode once in a while.
Soul Eater It doesn't happen all the time, but there are a few points in Soul Eater where the mood will do a complete 180 at the drop of a hat. sometimes even less
The second ending song can cause this as well: a sweet and rather bubbly tune about not wanting to grow up... which concludes, among others, all the episodes of the KishinRevival arc. Including the one that ends with the newly-revived Kishin showing off a Slasher Smile.
The series first Cerebus moment came when Soul got cut across the chest by Ragnarok. It's followed up by the fight between Crona and Stein and Death Scythe, which flips between the brutal and the comedic. Contrast Spirit stabbing Crona so that they are hanging from the blade or Stein blowing a hole through Crona's chest, with Crona and Ragnarok nonsensical mid-battle arguments and the bit where they wonder what to do with the stars circling Crona's head after being kicked by Stein.
The first 7 or so episodes of Sukisho make it seem like a cute, funny, Slice of Life anime. It comes as a complete surprise when the next 4 turn into horror. And then switches back to adorable for the OVA.
Sailor Moon mixes action, romance, and lots of comedy, so this isn't surprising. Super-Deformed slapstick in the middle of serious scenes, as well as shameless pantyshots could be narm or Narm Charm.
The reboot, Sailor Moon Crystal notably has this in episodes where an angsty/dramatic Cold Open is followed by the happier opening theme. Same goes for when a dramatic cliffhanger is followed by the closing theme.
There's a five-episode OVA called Master of Martial Hearts. The first four are fanservicey breasts-and-panties fighting anime stuff. The last episode is a neck-breakingly-fast shift into hard drama. It's as though someone called for a deconstruction in the planning stages and they didn't get to it until the end (though there are minor hints in that direction early on).
Sonic X, the original version, at least, has a fairly emotionally heavy ending to the second season, what with Sonic explaining to Chris why he stayed behind and Chris's reaction. Following into the dub-only season 3, which starts with... a really bad pun.
Angel Beats! frequently uses this. For instance, most of Episode Two involves the SSS members getting temporarily killed in increasingly bizarre and amusing ways (for the most part, no one can really die in Angel Beats! due to the fact that they're already dead, so this is Played for Laughs), but eventually, when it's just Yuri and Onatashi, Yuri starts talking about how when she was a little girl, her three younger siblings were killed by robbers right in front of her, one by one, because she couldn't find any valuables to give them.
Noda is such a psychotically violent Large Ham that he's basically Walking Mood Whiplash. One of the best examples is in the first episode, when Otonashi is about to join the SSS: the camera pans slowly across the other members while a stirring militaristic song plays in the background...suddenly, Noda bursts through the door, swinging his axe wildly and threatening to kill Otonashi (again) for insulting Yuri. And then a giant mallet smacks Noda out the window.
The beginning of episode 4 has Yui auditioning for Girls Dead Monster since Iwasawa moved on at the end of the previous episode. To counter objections she's too peppy and pop-ish for the role, Yui's audition is a rock version of the opening theme which shows she can pull it off. Then right after the end of the opening, she accidentally hangs herself with her own microphone by kicking the stand into the ceiling. "Death metal", indeed.
Rurouni Kenshin, similar to Fullmetal Alchemist, tends to have abrupt moments of comic relief interspersed with heavy drama and/or intense fight scenes. Compared to the manga, the anime adaptations have taken opposite approaches to this: the TV series significantly ups the comic relief, while the OVAs practically eliminate it.
There are plenty of scenes in High School Of The Dead where really serious and dramatic scenes will inexplicably cut to a panel of unleaded Fanservice. Occasionally, horror and fanservice will be shown in the same panel, like when a random girl is being eaten alive and the audience is treated to a Panty Shot from the victim.
A perfect example is at the beginning of chapter 6, which starts off with a radio broadcast about statistics about the infection spreading, which immediately cuts to the four main girls bathing together... with the very serious broadcast still playing over this.
Jack to Mame no Ki (An anime adaptation of Jack and the Beanstalk) does this from time to time, it starts out rather cheery and upbeat, once Jack gets to the beanstalk the mood changes after he meets Princess Margaret, after she sings a love song she introduces him to her "mother" a witch named Madame Hecuba who kidnaps children and feeds them to her ogre son Tulip, she has also taken over the kingdom of the clouds, murdered Margaret's parents, turned most of the servants into mice, and put Margaret under a hypnotic spell to which she will marry Tulip and inherit the castle.
The On the Next segments of Tiger & Bunny feature one of the titular duo cheerfully teasing the next episode while dropping in silly fandom nods, like how Kotetsu puts mayonnaise on everything and Barnaby saves his favourite food for last. Thus, there is a good amount of whiplash when we hear Barnaby saying, "Hi, I'm Barnaby - the member of Tiger & Bunny who always uses two tissues!" over shots of Kotetsu holding on to dear life in the ICU after being beaten into a coma during the episode proper.
And the show itself likes to switch between random silly humour, plot-less drama and dark, mysterious moments in consecutive episodes — sometimes even in the same episode.
The Future GPX Cyber Formula series does this often between the comedy/light-hearted moments and the dramatic/intense racing moments. The 3 OVAs also have these, although less than the TV series had. But by the time the final OVA SIN was released, there was almost all drama with little to no comedy left in it.
Kamisama Dolls pulls the whiplashes many times per episode, with the situation changing from comedic to serious (and vice-versa) at the drop of a hat. From the first episode alone, the expectations for what the anime actually is gets turned over enough times that you'll just learn not to take anything for granted.
Afganisu-tan can be this at points, particularly when you compare the childish pranks of the Nations as People with the real-life history that they're portraying.
Wandering Son thrives on this. You get a few moments of comedy before you go back to the melancholy feel of it.
Episode 40 of Tokyo Mew Mew. The previous few episodes were very dark and dramatic, and this episode has a more lighthearted feel overall.
In Tamayura, the carefree adventures of the main characters are often offset by Fuu's feelings of grief over her father's death, which is even more prevalent in the TV series than in the OVA.
Despite being a light hearted yaoi comedy with drama, Sekai-ichi Hatsukoi gets rather depressing especially around episode 16 where the aspect of the oblivious uke gets taken very seriously when you see what happens when you constantly try to show said oblivious friend that you're very serious with your feelings and get punished as a result.
Silver Spoon is filled with low key versions of this - every moment after an animal is introduced and fawned over by Hachiken, light-hearted talk of butchering and eating it ensue.
The fourth Hellsing OVA ends with the utterly horrific death of Rip Van Winkle and the invasion of London by Millennium. The credits then roll over a bizarre and utterly hilarious animated sequence of Schrodinger marching over the globe with Das Englandlied playing.
In the 8th episode, Alucard and Seras share a tender moment where he finally calls her by her name, indicating how proud he is that she's become a full-fledged vampiress and avenged Pip...and the scene immediatly afterward has Anderson screaming like a lunatic.
The 6th episode ends with a goofy and amusing credits sequence of Seras training with Pip and his men. This is followed by a scene where Seras finds the bloody corpses of those same men, and screams in rage at the person responsible
Sound of the Sky, unlike most anime, has a slow Opening and upbeat Ending theme. Cue episodes with horrible flashbacks near the end of the episode, followed by AIJOU YUUJOU
Where do we even begin with Heaven's Lost Property? In some instances going from a girl fretting about the boy she likes in one frame, and getting hit by a truck in another. Then you can go from a major battle, to a suicide attack, to this. Make sure you're wearing a neck brace when reading the manga.
Chapter 47 and 54 take the proverbial cake and eat it whole.
Life has a habit of having its few lighthearted moments followed directly by tragic ones. For example in one later chapter, Miki gets drunk at a festival. The next few pages are lighthearted until Miki and Ayumu fall down a cliff. Nothing bad happens, but they have a serious talk.. Then right after Miki barfs.
Kirby: Right Back at Ya! has an example of this. Episode 15 is about a toy dog that Kirby starts treating like his own child. The episode ends with the dog exploding and Kirby left devastated and mourning the dog. The next episode is a lighthearted episode about a fish who falls in love with Fumu.
The Idolmaster - Episode 19 ends with quite a predicament for Chihaya, but the ending theme, sung by Takane, is strangely cheerful.
Loveless has a habit of throwing in the occasional comic relief scene into what is otherwise a very dark series, though the anime does it more than the manga, and as of around Volume 6 onwards, these lighthearted moments have been getting further apart. It's Loveless after all, did you really expect the fluff to last?
The anime movie Ringing Bell starts out fluffy and cute — the protagonist is a naive little lamb with lots of energy — however it quickly turns into a dark revenge story.
Episode 2 of Maji de Watashi ni Koi Shinasai! introduces some of the main bad guys, and their scenes are very much more serious in tone than the relatively light hearted aspects of the school life stuff.
Smile Pretty Cure!, episode 21. Just when it looks like the girls will revive the Queen of Marchenland, Joker kidnaps Candy (and steals all but one Cure Decor), leaving them high and dry as Pierrot comes closer to awakening. Then we cut to the incredibly peppy credits song, and after that, the preview for episode 22 - which shows Joker tormenting Candy and the girls, a Nightmare Face, and Yayoi having a breakdown - set to the same peppy song!
It's not the only one - Heart Catch Pretty Cure had episode 44 - a Christmas Episode that also showed Cure Flower, the transformed state of Tsubomi's grandmother kicking copious amounts of ass. At the end, BOOM - the Big Bad finally makes his appearance. Cue Ending Theme. Then, the preview for the next episode shows the main heroines in tears because they blew it big time.
And there's also Pretty Cure All Stars DX 3, whose ending has six gathered teams bawling their eyes out because they just lost their fairy companions AND their powers to save the world. Then, there's a scene at the end where the fairies return, crashing another get-together.
Berserk: Days after blacking out during the horrible Eclipse, Guts awakens to Erika comically falling down the stairs of the elf mine in which he was brought to for safety. Moments later, Guts is horrified to learn that his lover, Casca, has gone completely insane due to being raped to insanity by their former commander and friend, Griffith, during the Eclipse. A major Freak Out! ensues.
Divergence Eve is a story of death, zombies, horrible, horrible things happening to everybody....yet the ending is happy jpop to the main character bouncing around in skimpy outfits. It is as if you replaced the end credits of Shindler's List with The Powerpuff Girls
Shin Mazinger episode 26. Kouji Kabuto delivers the killing blow against Dr. Hell with the awesome 100 Rapid Fire Rocket Punch and it seems that they've won. Then, we find out Baron Ashura is alive and he/she sacrifices themselves to resurrect the Mycene Empire and it ends on a cliffhanger with Mazinger Z rushing off to fight these beasts!
Episodes 13 and 14 of A Certain Scientific Railgun seem to be organized incorrectly. Both occur after the end of the "Level Upper" arc but Episode 13 is a Beach Episode while 14 is a slow, reflective episode that focuses on Ruiko Saten and her coming to terms with the events of the previous arc. Because of the intensity of the arc's climax, episode 14 seems to be a more appropriate follow-up but instead the series opts for a cheery, lighthearted, Fanservice-laden episode out of nowhere without really giving the previous arc a chance to cool down (which seems to be the aim of episode 14).
This trope is also used in the Sisters arc, when Mikoto's silly squabbling with one of her clones is followed by the clone being brutally murdered by Accelerator.
The first ten minutes of Kotoura-san anime is a Downer Beginning that systemically destroys the heroine's life and makes you think the whole show will be sad. Then you are suddenly launched into Manabe's goofy daydream, and the ludicrously cute and silly opening sequence. This sort of thing happens a lot.
This is common in Mohiro Kitoh's work. For example, in Bokurano, Machi tells Ushiro she has a crush on him. Then she gets shot in the head.
Near the end of Episode 20 of Saki, there's some relatively lighthearted shots of the teams getting ready to enter the individual tournament, with the first ending theme playing. Then the scene cuts to Shiraitodai, where they have effortlessly defeated their competition and Teru denies having a sister, suggesting that the rift between them is deeper than viewers and Saki previously thought. Then the scene shifts back to the pool, with Kiyosumi playing around and Saki hoping to see Teru again.
In Girls und Panzer, there's a fair amount in the tenth chapter. While they're getting ready for the match with Pravda, there's some lighthearted moments as they try to acclimatize the new Duck Team. Then Momo insists that they have to win and gets angry when some of her teammates doubt that they will, at which point she insists that it's absolutely necessary, and Anzu reaffirms this with uncharacteristic seriousness. Then Yukari, the POV character of the manga adaptation, briefly reflects on all the friends she's made through tankery, and how fulfilling her life has become in the past year. While Yukari is doing so, she notices Miho talking with one of her family maids, then follows the two into a restaurant when she sees Miho's expression change suddenly. While the meeting between the two is initially pleasant Miho's maid then tells her that her family has decided that if she does not win against Pravda, she will be disowned.
The Buu Arc is just ripe with Mood Whiplash's. The tone of the episodes change from comedy to action to heartwarming to drama almost every other episode. Majin Buu debuted as a pink, fat, childish, candy loving blob monster, just moments later he turns Dabura into a cookie and then eats him, almost kills Super Saiyan 2 Gohan and nearly beats to death Majin Vegeta and one of the rulers of the Universe, Supreme Kai.
Another example, Buu Arc specific, also being when Mr. Satan convinces Majin Buu not to cause anymore destruction by explaining what the differences are between good and bad. Majin Buu not only agrees to never kill again but also starts to show his side of love and compassion with a new dog the he and Mr Satan had adopted when Majin Buu healed it. Then the dog is shot at the end of the episode.]
The scene where Old Kai sacrifices his life to bring Goku back to life is played as a Tear Jerker until he suddenly gets back up and angrily tells Goku to hurry up.
Dragon Ball Super, is steeped in mood whiplash. Most of this results from the introduction of Beerus and Whis, introduced in the first story arc as villains and hands-down the most powerful beings in their particular universe (though not, by any means, within the multiverse). In subsequent arcs, their power could be a story breaker that would instantly solve any plot, but they just aren't interested in helping the main characters, so they spend most of their screentime as Those Two Guys making wry comments about plot developments and getting into amusing antics on the side. The whiplash gets even stronger in the "Future Trunks" Arc, which features the show's most seriously evil villain so far and is set in a very depressing Bad Future. This plot is interspersed with Beerus and Whis's interactions and an entirely humorous plot involving the King of Everything wanting to be Goku's friend, all part of the set up for a Tournament Arc later on.
Umi Monogatari has this setting in from the solar eclipse episode onward. What was once a happy, gentle show takes a turn for the scary.
Used in The Testament of Sister New Devil. One scene may consist of a romantic comedy harem high school theme. The next suddenly has the characters fighting for their lives against demons.
Yamada-kun and the Seven Witches is always reasonably light-hearted, but has some serious and sad scenes once in a while. During these scenes, there will almost be someone who temporarily breaks the seriousness by saying something (unintentionally) funny or making an cartoonily exaggerated reaction face. Sad moments suddenly interrupting comedic moments also happen now and then.
Kantai Collection infamously does this in its fourth episode. During the emotional fallout of the death of one of the characters, the quirky Kongou siblings bust in the middle of the episode and end up hijacking the show, not addressing the deathuntil the end. It wasn't as bad as one would think, but they certainly left a mark.
The anime adaptation of JoJo's Bizarre Adventure Stardust Crusaders puts Terence D'Arby's defeat and Vanilla Ice's introduction within the same episode. D'Arby gets comically punched out of a celling by Star Platinum, whereas Ice unceremonially kills Mohammad Avdul and leaves the ending as a cliff hanger.Knight of Cerebus is so suddenly placed even the manga readers 25 years ago may find it shocking, let alone the anime-only audiences.
The trope applies to Stardust Crusaders in general. While the protagonists are thrust into serious situations, there's a fair amount of humor and sense of semi-danger that assures readers/watchers that in the end, no serious harm will befall the characters. Towards the end of the series, the cast starts dropping like flies immediately after the fight with D'Arby the Younger, and with the exception of the scene of Joseph's revival, humor is virtually absent.
In Guardian Fairy Michel, the trailer has pretty shots of the Tree of Life and talks about nature and a boy who protects it... then giant sci-fi robots. And then back to the tree.
Momotaro's Divine Sea Warriors starts out with adorable animals doing everyday things, but then Momotaro arrives in a plane and suddenly it turns into a war film.
In episode 2, Aya refuses Wakatake's request to write a notice for a lost bicycle because she thinks Wakatake is being snobby and Wakatake's bicycle has nothing to do with her anyway. Then Wakatake apologizes, saying he makes the request because he thought she is "one of us," and went downstairs. Aya then realized she may have been losing potential friends for being Innocently Insensitive, as Wakatake treated her as a friend but not vice versa, and Wakatake's the first person who called her a friend. So she chased downstairs, only for her to realize Wakatake wasn't known for egging people on for nothing:
Wakatake: Do you feel like writing the statement now?
Yo Kai Watch episode 25 ends with Nate and Jibanyan dreamily running toward each other like when they first met, only to be interrupted by Nate's mother finding Jibanyan ate her chocolate cake, assuming Nate did it and cutting him off from desserts for a week, leading to Nate and Jibanyan getting into an argument.
Daddy... please pray for me. That this surgery will work out.
My Monster Secret loves doing these, building up extremely dramatic moments only to completely derail them immediately after. Even genuinely serious moments tend to be be followed by heavily comedic ones. A good example is the arc where Nagisa receives an order to leave earth and spends a couple of chapters coming to terms with having to leave her friends and is rife with both heartwarming and tearjerking moments. Then the very last page of the last chapter of the arc reveals the whole thing was an April Fools' Day prank by her brother Gone Horribly Right.
In Chapter 113 of My Hero Academia, after the Provisional Hero License exam ended, the students check the monitor to see their names, meaning that they've passed the exam. On the last page, were treated to a shocked, comical expression of Izuku Midoriya as he sees his name, but Shoto Todoroki and Inasa Yoarashi are both disappointed not to see their's. Notably, the panel with Todoroki looking sadly at the monitor is directly below Midoriya's, driving the contrast even more:
Destruction Flag Otome is a lighthearted comedy series about a girl reincarnating as a literal otome game villain but turning into a Blithe Spirit who amasses a giant harem instead of getting killed off like she's supposed to. However, one chapter cuts away from this back to her past life as we see her best friend grieving for the first friend she ever made, though at the end she does come to terms with it.