A Stock Phrase usually uttered in comedies. Basically, someone has learned something strange about another character, but rather than being surprised or shocked, they take it in stride. Why? Because it actually explains a great deal of the odd characteristics of the character in question.
Compare with Eureka Moment.
- In Dragon Ball Super, Goku remarks that he appreciates his wife Chi-Chi being strong-willed, and Vegeta (whose wife Bulma is the same way) states that Saiyan men are naturally attracted to strong women, since Saiyan women were similarly strong. Piccolo, who's standing in the background, gets a Jaw Drop as he thinks to himself "That. Explains. EVERYTHING!"
- In K-On!, this is Azusa's reaction when she learned that Sumire used to bring Mugi manga. Said manga is implied to be yuri manga.
- In the fifth-to-last episode of Sonic X, this is exactly what Sonic says after he has been listening in on Hertia/Earthia telling a story to Amy and Rouge about how her former home planet Seedrius-Flora/Greengate got destroyed and how the Metarex, the main villains of the third season, came into the picture.
- In Tiger Mask W this is Miss X' reaction when she learns the new Tiger Mask has been trained by a former Tiger's Den wrestler, as it explains why he's as strong as if he had been trained by Tiger's Den.
- In To Love-Ru, this is just about every human character's response to learning that Lala is an alien.
- Upon the Straw Hats meeting Garp in One Piece, Luffy's grandfather, they find out about the Training from Hell he subjected his grandson to at a very young age. They all then realize where Luffy's stubborn refusal to die comes from.
- In the Mickey Mouse Comic Universe science fiction saga The Lords of the Universe this is Mickey's reaction when Goofy is revealed to be one of the twelve Masters, as it confirms he has extraterrestrial ancestors (something Mickey had actually suspected for a while).
- In the Castlevania fic Blood Relations, Soma and Mina have this reaction when they find out Arikado is a vampire (strictly speaking, he's a dhampyr, but they don't know that and it's a little more information than he's willing to share).
- When Hitsuguya finds out that Ichigo's inner world is normally tilted on it's side in Ichigo, Meet Ichigo, he says, "I suppose that makes sense, now that I think about it."
- In Magnetism, this is what Fluttershy realizes when she remembered Rainbow Dash spent the week long sex ed lessons sick.
- In National Sercurity, Neal wonders how America/Alfred ended up the way he did (while unaware of national personifications). When he hears Alfred's former guardian over the phone swearing and desperately chasing Tony while chanting a bizarre spell, Neal thinks that it explains everything.
- Yu-Gi-Oh! The Abridged Series:
Iruka: Guess what Hokage, I was the guy who test screened the 4Kids One Piece dub!
- This response to Duke Devlin's desire to avenge Pegasus.
- During the matches on Kaiba's blimp, Tristan assumes they're in outer space. Then Bakura summons Dark Necrofear, a gaunt, sallow and thin figure...
Tristan: Ahh! It's an alien! Just like the ones that abducted me when I was a child.
Tea: That explains so much, and yet so little.
- Then later, during the Virtual World Arc, when Team 4Kids states that their test audiences loved their dub of One Piece, the scene switches to Iruka and The Hokage from Naruto: The Abridged Comedy Fandub Spoof Series Show.
Hokage: That makes way too much sense.
- In A Door Jam, Twilight and Applejack give each other a look that says this when they hear that Pinkie Pie hits her head on her ceiling every morning.
- In the One Piece fanfic This Bites!, Luffy offhandedly tells Chopper that his grandfather taught him that concussions are harmless (they're not). Self-Insert Cross groans that if Garp really believes that, it explains much about Luffy's Idiot Hero status.
- In Ice Age 4: Continental Drift, after Sid's family leaves Granny with Sid and the herd and abandon him for the second time.
Diego: Well, that explains a lot about Sid.
- In My Little Pony: Equestria Girls Legend of Everfree, Sunset, who has just gained the power of Touch Telepathy, has her hand grabbed and put on Pinkie's forehead...only for the screen to be assaulted by an image of Pinkie merrily skipping through a land where everything is food and in the midst of a perpetual party. Eventually, Sunset quietly removes her hand and remarks:
Sunset Shimmer: That explains so much.
Pinkie Pie: Yep!
- Shrek has this reaction to Fiona turning into an ogre near the end of the first movie.
- Planes: Upon being told Chug came up with the "Strut Jetstream" nickname for Dusty, Dottie says it explains everything.
- In Almost Famous, William's response to finding out that his mother has been lying to him about his own age so that he wouldn't know that he'd actually skipped two grades is literally "This explains so much."
- From The Boy Who Cried Werewolf, regarding Britney Spears:
Madam Varcoloc: She's a werewolf, you know.
Hunter: That explains a few things.
- Men in Black:
- At the end of the movie, J offhandedly mentions to L that Dennis Rodman is an alien, which results in this:
L: The high consulate from Solaxium 9 wants seats for the next Bulls game.
J: Let's put in a call to Dennis Rodman. He's from that planet.
L: Rodman? You're kidding.
L: Not much of a disguise.
- And earlier, J gets this realization that his 3rd grade teacher was an alien, which he's suspected all along.
- When Dr. Weaver and J see that the man she was performing an autopsy on was actually a human-shaped transportation unit for a dying alien, Dr. Weaver starts muttering to herself about how the presence of aliens makes so much sense, because "how else can you explain New York?"
- At the end of the movie, J offhandedly mentions to L that Dennis Rodman is an alien, which results in this:
- In Mr. Deeds, Longfellow Deeds persuades a packed boardroom to remember their childhood dreams and ambitions, and one of his neighbours, a denim-and-flannel-shirt-clad woman announces that her wish was to become a man. Deeds' response is justified.
- When Shakes disguises himself as a mime in Shakes the Clown to search for clues to the solving of a murder at a mime school, his two friends nearly beat him to a pulp (mimes are subject to Fantastic Racism in this movie) before realizing who it is - and even then, they remain disgusted, with one of them remarking that he suddenly understands "all those times he would just sit there saying nothing." But Shakes finally manages to persuade his friends that he's still a clown.
- Some Kind of Wonderful has this darling piece of dialogue:
Ray: If you wanted to, you could be a girl...like that!
Watts: Ray, this is 1987. Did you know that a girl can be whatever she wants to be?
Ray: I know, my mom's a plumber.
Watts: That explains a lot about you, Ray.
- Gravity Falls: Journal 3: Dipper's Observation #1 about Quentin Trembley. "Haircut by his third wife, Sandy. (She was a woodpecker. That explains a lot.)"
- In an episode of 3rd Rock from the Sun, Dick discovered he was Canadian in his phony Earth identity. When he told Mary that he was Canadian, she said that it explained all his weird behavior.
- In the first episode of the last season of 30 Rock, Jack explains that he's been deliberately "tanking" NBC, so that it will turn into a money-losing embarrassment and the owner will have to sell it.
Liz: This explains everything! How long has this been going on? Seven years? Eight?
Jack: Six weeks.
- Angel, as Spike demands an office at Wolfram & Hart:
Spike: At least give me Wesley's office, I mean, since he's gone -
Angel: He's not gone, he's on a leave of absence.
Spike: Yeah, right. Boo hoo. Thought he killed his bloody father. Try staking your mother when she's coming on to you!
Harmony: Well. That explains a lot.
- When Felicity Smoak of Arrow learns that Oliver is The Hood, she has this to say:
Felicity: Everything about you just became so unbelievably clear.
- Buffy the Vampire Slayer:
Xander: Yes, vampires are real, there are a lot of them in Sunnydale.
Willow: I know this must come as a shock...
Oz: Actually, it explains a lot.
- After Mike meets Susan's rather... flighty mother in Desperate Housewives:
I had a bunch of questions about you. They were all just answered.
- In an episode of Hannah Montana, Lily and Miley are sitting in front of their computer when they receive a video e-mail from their teacher Mr. Corelli reminding them about International Relations week at school. During the course of this video, it is revealed that he still lives with his mother and is somewhat nerdy. This causes Lily to remark "This explains so much."
Tony: You know, repeated head trauma causes brain damage?
- After Tony gets Dope Slapped by Gibbs:
McGee: Explains a lot.
Gibbs: Are your brothers really like that?
- In another episode, after Kate compares Tony and McGee's bickering to her two "practically psychotic" older brothers:
Kate: Sadly, yes.
Gibbs: Explains a lot.
- In the last episode of Season 10 of Red Dwarf, we get a hell of a revelation that Rimmer's father really wasn't his father; it was actually the idiot family gardener, Dungo.
Lister: And suddenly a billion-piece jigsaw puzzle falls beautifully into place!!
- Subverted on an episode of Star Trek: Deep Space Nine. Kira has recently learned that Odo, whom she has been working alongside for quite a few years has been in love with her the whole time, and is taking some time to figure out what to do about it. When she tells Jadzia about it, this conversation results:
Jadzia: That explains a lot.
Kira: What do you mean?
Jadzia: ... I don't know, really. It just seemed like the thing to say.
- In an episode of Wizards of Waverly Place, Justin tells Harper that Alex thinks that there are no rules if you're on an island, prompting this exchange:
Harper: But you live on Manhattan Island.
Justin: I know. Doesn't that explain a lot?
- Mass Effect 2: When Shepard and Tali discuss the geth situation with quarian admiral Daro'Xen, she snaps that someone experimenting on (sapient) machines should feel no more guilt than she did performing surgery on her childhood toys. Tali provides the stock phrase.
- In the lead-up to World of Warcraft: Legion, it is revealed that the entire world of Azeroth itself is more just a "hunk of rock", rather, it is actually a titan, one of the race of beings who created the world, and one of which leads the Burning Legion. Khadgar is shocked at first, but notes "That...actually explains a great many things."
- In Metal Gear Solid 2: Sons of Liberty, taking a picture of one of the male pinup posters as Snake and sending it to Otacon will prompt him to remark, "So...this explains a lot."
- Red vs. Blue:
- In Season 5, when Sister first shows up, she comments that her and Grif's mother was in the circus. Prompting Simmons to respond, "You've already made my insults 45% more efficient by just saying one sentence."
- Back in Season 2, Doc is less confused once he learns that the Reds "ran out of water months ago" and have been drinking nothing but soysauce, ketchup, and gravy.
- In Season 14's "Meta vs. Agent Carolina" prologue, Grif and Simmons learn that Carolina is the daughter of Tex, and Simmons remarks, "Huh...suddenly everything makes a lot more sense."
- Variant phrase, same sentiment in 8-Bit Theater. After Black Mage has been hit by what Red Mage describes as the dreaded "Goblin Punch".
Thief: You called it a Goblin Punch. Even though it was clearly a kick. And there isn't a goblin around for miles.
Red Mage: What? That's the name of the attack, as laid down by the greatest Red Mage cryptozoologist of all time: Blindy O'Sightless.
Thief: The more I learn about you, the more it makes sense.
- In Captain SNES: The Game Masta, Mario has this reaction when hears about the number of times Max Force had been hit by hallucinogenic drug-filled needles in his war on drugs. Alex states that this is the tip of the iceberg.
- In Darths & Droids when Qui-Gon (played as an idiot kleptomaniac) suggests that he acquired his laser sword by killing a Cheddar Monk and taking it from him. Padmé/the DM says "You know...that would explain a lot".
- In the Castle Heterodyne Arc of Girl Genius, Agatha, Gil, and Tarvek find the Heterodyne Nursery which has a rampaging huge, steel-clawed, shoulder-spiked jack-in-the-box clank that acted as a nanny to the bloodthirsty, murderous Heterodynes. After it finally stops wrestling with boys, Tarvek comments on the trope.
- Used at least once in Andrew Hussie's second-person webcomic Homestuck: "You suddenly understand everything."
- Subverted in Questionable Content, when Hanners reveals that she grew up on a space station. (Her dad is a Mad Scientist.)
Faye: You're actually from space?
Hannelore: Yes. I'd say "That explains a lot, doesn't it?", but it really doesn't.
- In The Annoying Orange video Introduction To "Ultimate Dog Tease" (when Marshmallow and Midget Apple have just watched Bizkit the Sleep Walking Dog):
Marshmallow: Yay! I love Bizkit!
Midget Apple: You think Bizkit's gonna be okay after bashing his head against the wall?
Marshmallow: Ooh! I love bashing my head against the wall!
Midget Apple: That explains a lot, actually.
- In Bibliography, Raoul answers that when he learns that his Super Strength came at the price of his sense of direction: A moment earlier, he had gotten spectacularly lost.
- CollegeHumor: In one of the jeggings videos, where teenagers keep coming to school wearing inappropriate clothing, the exasperated teacher eventually asks them what their parents have to say about it. When one of them confesses that all of their parents have died, he pauses and admits that does make sense.
- The Spoony Experiment: Spoony's reaction in his "Let's Play Phantasmagoria 2", after the big reveal that the otherwise bland, dorky PC Curtis Craig is literally not of this world.
Spoony: So let's see if I have this right—according to Warner, Curtis is really an alien made out of slime and rat testicles? ... That actually explains a lot.
- Archer on the subject of Archer's Freudian Excuse.
Malory: 'cause he'll be back! Crying for his mommy! Just like that Christmas break when I moved and forgot to give my new address to his stupid boarding school. I mean, he rode the train into the city all by himself, he couldn't pick up a phone book? 9 years old and bawling in that police station like a little girl! Huh - what's that tell you?
Cheryl: Kind of a lot, actually...
- There are many times when Malory does something to which another character (sometimes Archer himself) states "A ton of stuff started making sense [about Archer's behavior]", or something to that effect.
- There's also several instances where Archer questions if he's on the Autism Spectrum, as he finds himself being the only one able to identify weapons at a glance, keep track of bullet counts, and other such things when in battles. Most people when they hear this theory usually say something along the lines of "Huh. That would explain a lot."
- In the CatDog special "Great Parent Hunt", Rancid Rabbit hosts a fair on Parents' Day, where the show's recurring characters bring their parents. Lube brings his parrots. Thinking Lube misheard, Rancid explains he was supposed to bring the people who raised him and made him what he is.
Lube: Duh, yeah...parrots.
Rancid: This explains all so much.
- In the Big Boogey Adventure movie of The Grim Adventures of Billy & Mandy, The Grim Reaper notes that love makes people do stupid things. Billy then declares that he loves everything...which Grim retorts explains a lot.
- Used to the point it's a Running Gag in Johnny Test. For example, in one of the race episodes, Gil reveals to his partner, Bling-Bling, that "[He] was raised in the wild by gorillas!"
Bling-Bling: Huh. That explains a lot.
- My Little Pony: Friendship Is Magic: it was revealed in "Lesson Zero" that Twilight Sparkle's favorite toy as a child, Smartypants, came with a miniature notebook and quill so you could pretend she was doing her homework. This trope is how the Cutie Mark Crusadersnote reacted.
- The Rocketeer: In "Hypnotic Hughesville", The Great Orsino has this reaction upon learning chickens are his assistant Deany's favorite animal.
- Steven Universe: In "Made of Honor", Bismuth is initially shocked when Steven tells her about Rose Quartz and Pink Diamond being the same person, but after he further explains everything, including the Corrupted Gems, she realizes that everything makes perfect sense, since The Reveal fills in a lot of logical holes and explains what happened between her and Rose.
- From an episode of Sushi Pack:
Ben: If you want to wear one later, Tako, just speak up.
Kani: Yeah, we can't read your mind!
Tako: There's nothing to read.
Kani: That explains so very, very much.
- In the Muppet Babies (1984) episode "He's a Wonderful Frog", Rowlf tries to read a book to Kermit about Kermit's life, but finds that the book contains various nonsensical and inaccurate details, such as Kermit being raised by wolves and being elected emperor of California. It turns out that the book was put together by wannabe comedian Fozzie and Cloudcuckoolander Gonzo, which causes Rowlf to remark that that explains the book's absurd inaccuracy.
- From The Simpsons episode "The Front":
Homer's brain: This is it, Homer. It's time to tell her the horrible secret from your past.
Homer: Marge, I ate those fancy soaps you bought for the bathroom.
Marge: Oh, my God!
Homer's brain: No, the other secret!
Homer: Marge, I never graduated from high school.
Marge: That still doesn't explain why you ate all the soaps. (sadly) Wait, maybe it does...
- Seen in this short video of Kiefer Sutherland in a state of extreme intoxication.
- The great many, many things that happen out there that seem strange or questionable out of context but have this trope behind it.
- This is a very common response for people with autism-spectrum disorders who don't get diagnosed until adulthood.