Being in love is dangerous for a character. Occasionally, a 'main' character who more or less pulled his weight at the start of the series starts to feel affection for another, and the writers like the idea. Suddenly, his own personal plot starts to become almost exclusively about that, and we have nothing to balance out the inherent goofiness and clumsiness that occurs dealing with his emotions. This has an extra layer of trouble if the Demographic of the viewers isn't too heavily interested in the romance, or romance in general. On the other hand, other demographics can relate.
This can send someone on the edge of Can't Catch Up straight into a ditch and relegate him to the side lines of a story, especially if it's fairly clear that the writers haven't used the character for a while because they don't know what to do with him.
If it isn't focus where they're hurt, it'll be their common sense, as suggested by the trope title. The love interest may be all wrong for him in reality, anything from making him, or trying, into something he's not, or worse, outright using him. When friends of the character try to snap him out of it, they will be accused of jealousy by the lovestruck victim.
- In InuYasha, Sango commits some major blunders as a result of her concern for Kohaku and Miroku. These result in nearly getting herself and them killed on a few occasions, as well as nearly murdering Rin.
- Dragon Ball Z: Krillin had the chance to shut down Android 18 and stop Cell from ever reaching his Perfect form. But because he developed feelings for her, he destroyed the only chance to stop it from happening.
- Shuro from Delicious in Dungeon starts seriously neglecting his health and running himself ragged while on his quest to rescue Falin, who he's in love with, from the dungeon. In the end he's so badly off that he has to return to the surface and leave the search to Laios's party.
- At one point in the Yu-Gi-Oh! GX anime, a creature was introduced that literally made other creatures dumbstruck with love. She was (appropriately) called the "Maiden in Love" and any creature (male of course) that attacked her would then fall under the control of the player using the Maiden.
- Miyagi, Sakuragi, Aouta and Haruko in Slam Dunk. The mention and/or sight of their crushes can make them reach varying stages of ditziness, no matter where they are. Of course, according to fangirls, in the boy's cases it's sweet and funny, and in Haruko's case is a horrible sin.
- Ohgi of Code Geass was the voice of reason of the Black Knights, until he encountered and fell for Villetta. Needless to say, he became one-track minded soon after and made some incredibly rash decisions, not the least of which resulted in Lelouch being betrayed by the Black Knights.
- Dr. Tofu from Ranma ½ is arguable, since one of his traits from the start was the inability to function properly around Kasumi. Swiftly becomes a moot point, once he's replaced as the show's source of arcane knowledge by Cologne.
- Ryoga Hibiki does some pretty dumb things because of love as well. His unrequited desire for Akane's heart is his biggest emotional target, and he tends to go crazy when he thinks there's some sign she truly does love him back. At one point, he even considered staying in the Cursed Tunnel of Lost Love because Akane was frightened by the ghosts and kept clinging to him for protection and comfort — he figured that if he and Akane stayed there forever, she would always be turning to him for comfort. He gave it up mainly because the others caught him before he could run off with Akane and get lost in the tunnel.
- Rosario + Vampire:
- Tsukune Aono before his power up. He doesn't come off as dumb at first, but common sense and obvious logic are trumped whenever Outer Moka is in trouble. We're talking to the extent he would take on the equivalent of a M1 Abrams Tank with a slingshot. He never gives up despite how bad the last time was.
- Likewise, the various members of Tsukune's Unwanted Harem often end up doing some pretty idiotic and non-logical things in their attempts to win him over. For example, in Capu2 episode 8, Mizore, Kurumu, and Yukari get in a big fight in the human world over him and end up nearly breaking The Masquerade when they decide to use their powers; the fight escalates to the point that Tsukune has to unleash Inner Moka to get them to stop; Inner Moka outright calls them "stupid, immature brats" before K.O.'ing all three of them at once.
- This is pretty much the entire plot of School Rumble. And neither Kenji nor Tenma was particularly bright to start with, leading the series down some truly bizarre roads.
- Esmeraude (Emerald) in Sailor Moon R. She was so in love with Diamond that she hastily accepted Wiseman's tiara to become more powerful than Sailor Moon and thus, winning Diamond's heart. Unfortunately, her plan falls apart when the tiara transforms her into a dragon rather than a Queen. The senshi (with the help of Tuxedo Mask) defeat the dragon and Esmeraude is momentarily restored to her human form - only to fall into a dark abyss. She whispers Diamond's name as she vanishes. To Esmeraude's credit, the rest of her peers including Diamond also made the colossal mistake of trusting Wiseman.
- In Parasyte, it's Kana Kimishima, whose Spider-Sense could have become the best tool there is to keep herself safe from the abnormal Parasite hosts blended in society. What does she do with it? Use it to become a complete Stalker with a Crush for Shinichi whenever she senses Migi. Her love makes her so dumb that it leads to her getting killed by a random Parasite she thought was Shinichi.
- Brock in Pokémon, who is usually the rational Big Brother Mentor to Ash and Misty (or May, Max and Dawn), tended to lose his cool around beautiful women; especially Nurse Joy or Officer Jenny (and since both are everywhere, this quickly became a running joke with him proclaiming the latest one was the fairest of them all).
- Any Pokémon under the effects of Attract can be seen making a fool of themselves in the middle of battle. This becomes an In-Universe That One Attack that easily gives the attacker an easy victory over their opponent, but none of the characters conveniently realize this, not even the main Chaste Hero.
- From the strange and supernatural manga, Sex Pistols, one part-time protagonist Seth decides, after his boyfriend tries to break up with him, to knock-out said boyfriend, kidnap him, take him half-way across the world into a war zone in Saudi Arabia, lock him up, and then forget to tell him that the reason why he's locking him up is that as soon as he entered the country an entire faction of Seth's family have been trying to kill him! Nice one, Seth. And no, he wasn't aiming for an If I Can't Have You... ideology either. Probably.
- In the Area 88 manga and OVA, Ryoko has very idealistic and immature ideas about love. To boot, she is determined to free Shin from servitude at Area 88, but never stops to ask why he might be in the Asranian air force in the first place. Finally, in manga issues that did not make it stateside, Shin repeatedly breaks her heart, and yet she reunites with him in the end.
- In the manga, Kanzaki even calls her out on it.
- In Pokémon Adventures, Malva is an extremely competent Dark Action Girl, though it's also very clear that she wants to be in an Unholy Matrimony with Lysandre. During the final battle, Lysandre is falling to his death. As Malva's distracted, the Talonflame she's riding goes down and she then leaps, unassisted, towards her boss. Diantha tries to save her, but Malva slaps her away. All Malva ended up doing was seemingly getting killed alongside him.
- Kaguya-sama: Love Is War: In preparation for Shirogane's birthday, Kaguya buys him a huge birthday cake in the style of the one that Fujiwara had for her birthday. Hayasaka recognizes the overkill immediately, and it's only right before she gives it that Kaguya remembers that Fujiwara's birthday cake was much smaller—and much less embarrassing. While she mulls over what to do, Kaguya imagines a court case between her "cold side" and her "dumb side," evoking a Good Angel, Bad Angel conflict. Her dumb side advocates fiercely to give Shirogane the cake, being open, honest, and insistent about Kaguya's love for him.
- In Supergirl/Batgirl story Elseworld's Finest: Supergirl & Batgirl The Joker is infatuated -and obsessed- with Batgirl (who in turn hates his guts). His intelligence drops down to negative digits when Batgirl is nearby, makes real dumb statements and gets distracted during fights.
- In Superman story Kryptonite Nevermore, a pilot tries to fight three armed bandits to impress Lois Lane. He has the chance to catch them off guard... and he shouts before pouncing on the ringleader.
- Scott Pilgrim plays with this trope. Granted, the titular character is already kind of dumb but one can also see this trope in Knives Chau.
- Monkey Khan in Archie's Archie Comics' Sonic the Hedgehog, he gave up the Power Ring he uses to make sure that Eggman or the Iron Queen can't control him due to his mostly cybernetic body. He lets himself be controlled by Eggman just so Mecha Sally won't die, despite the fact that Mecha Sally has no remorse or inhibitions and will happily kill him despite the brief relationship Sally and Khan had.
- Chakra in Les Légendaires: Origines combines this with Love Makes You Evil. She has a Bodyguard Crush on her hirer Prince Halan, but he only has eyes for Princess Jadina. So what does she do? Well, she helps Big Bad Darkhell to kidnap Jadina. Also, she contacts him through his Lizard-looking Dragon. And even worst, when he offers her a meeting at night, alone, far from the castle, she accepts without taking any measure to ensure her security. So there isn't much surprise when, after she handed over the information, said Dragon lampshades this trope before having her Rewarded as a Traitor Deserves.
- The root of Hayseed Turnip's problems in the short story in My Little Pony Micro Series Issue #3 , as every time he faces Rarity he ends up doing or saying annoying things that upset her, much for his dismay.
Hayseed Turnip Truck: She was a vision... The most perfect pony I'd ever seen... and I blew it.
- From Astro City, the brilliant Mock Turtle is blinded by love for his childhood sweetheart Lucia, who he constantly imagines as an innocent girl to be sheltered from his roguish life. She, in turn, easily exploits his intellect and engineering talents for her own gain.
- Advice and Trust: Ritsuko is a very smart and resourceful scientist... but she has fallen for Gendo and has deluded into thinking Gendo does or will love her back... even though he always treats her like crap at best and an useful but disposable and ultimately replaceable pawn at worst, and he has provided her with plenty evidence that the only woman he will ever love is his deceased wife. Still she repeatedly tells herself: "He will love me. He must! He needs me!"
- A Crown of Stars: Shinji and Asuka develop a rather "enthusiastic" relationship in later chapters; probably making up for years of Belligerent Sexual Tension. However, they get so wrapped up in their passion that they forget a few things - like using birth control, or that Asuka's future self had been pregnant when they met. The inevitable finally occurs in chapter 67, and both agree that they should have seen this coming.
Asuka: (Now what, Sohryu? Im so fucking smart, now what do I do? Ive been bragging to myself about beating fear and deciding my own fate for weeks now. I think fate just punched back.)
- Rosario Vampire: Brightest Darkness: In Act II, Tsukune's ghoul form exploits this trope upon realizing Kokoa's newfound feelings for Tsukune, secretly takes over Tsukune's body, falsely declares his love for her, and ultimately tricks her into giving him a blood transfusion while using her newfound overcharge, successfully giving it enough power to become a full-fledged ghoul and hijack Tsukune's body completely; just as the ghoul was expecting, Kokoa is too blinded by her feelings for Tsukune to realize she's just an Unwitting Pawn until it's too late. By the very first chapter of Act III, when she realizes her mistake, she's so devastated that she nearly kills herself, and after Tsukune gets a Holy Lock to suppress the ghoul, declares herself Tsukune's servant in penance.
- In Thousand Shinji, Shinji and Asuka were so infatuated with each other that Shinji didn't notice his father was scheming against him.
Rei: During that time, when everyone was distracted, your father had your apartment laced with monitoring equipment. When you got back, instead of sweeping for bugs like you usually do, you and Asuka had celebratory sex,
Shinji: Fuck. Fuck! Fuck!
Rei: That was your problem,
- Fade: Light is so blinded by his love for L that he keeps going along with L's schemes and Insane Troll Logic justifications for acting like Kira, despite knowing what he's doing is wrong, partially motivated by the belief that he can "fix" L. He also refuses to see the signs that the relationship between them is unhealthy and potentially abusive.
- Shang in Mulan is a mild form of this trope. He is a competent and professional soldier, not even letting his father's death distract him from the task at hand. But when he tries to thank Mulan after saving him from Shan Yu and when he later visits Mulan's house, he stammers and generally has no idea how to act around Mulan now that he knows she's a girl.
Shang: You...you fight good.
- The titular character in Roadside Romeo. His love interest tells him that if he truly loves her, he'll have to sing on stage with her at a club. When he gets there, his friends desperately tell him not to because he'll make the Big Bad furious and bring out his jealousy. Romeo has to decide to walk away from the dog and find someone else, or risk his life for someone he's only met twice, and has only known for about three minutes. Guess what happens.
- Sherman in Mr. Peabody & Sherman: Mr. Peabody is quite surprised that Sherman eagerly tried to save Penny from marrying King Tut, especially when she wouldn't even give him the time of day. However, when trapped inside a pyramid, a bashful Sherman wants to give up, and Peabody's questions lead him to act very goofy.
Sherman: Give me a break! It's not like I want to hold her hand, or go to the park... or watch her while she's brushing her hair...
- In The Secret Life of Pets Gidget the lovesick Pomeranian does very crazy and impulsive things to rescue Max, including jump out of her apartment room on a high floor, assault an alley cat after just meeting him, confronting an evil bunny and telling him about her and her team's relationship with Max, and, if not the most wanted crazy thing, singlehandedly overpower a group of animals that greatly outnumber her.
- Played for Drama in Kung Fu Panda: Shifus love for his adoptive son, Tai Lung, blinded him to both Lungs growing personal issues and the possibility that Lung wasnt cut out for being the Dragon Warrior. He filled Tai Lungs head with dreams and put him through decades of brutal training... than had no answers when Oogway frankly stated that Tai Lung was not the Dragon Warrior. Tai Lungs response to that was disastrous.
Shifu I have always been proud of you... From the very first moment, Ive been proud of you. And it was my pride that blinded me. I loved you too much to see what you were becoming. What... I was turning you into. I'm... I'm sorry.
- Hellboy II: The Golden Army: Oh, Abe Sapien. Friend or Idol Decision, Hostage for MacGuffin, The Villain's Sister and here you were making a fool of yourself for love.
- Crazy Stupid Love: It's even there in the title.
- A Knight's Tale: William fully understands this trope, as after offering to be Jocelyn's Champion (a line she's heard way too often), she tells him that if he loves her, he'll lose. And so, at the beginning of the next tournament, after the flag for William's first joust is dropped, and his opponent spurs on, the four members of the Five-Man Band cheering William on...
Roland: "What are you doing?"William: (sitting on his horse, going nowhere) "...Losing."Wat: "I don't understand."William: "...Neither do I." CRASH!
Geoff: "There she is, your symbol of love. Your Venus!"William: "And how I hate her."
- This leads to a subversion later on, when Jocelyn changes her mind mid tournament and tells him to win the tournament he just spent the day losing in the most painful way.
- In Stargate Continuum, Baal uses Time Travel to maneuver himself into dominance of the Goa'uld System Lords and is in position to conquer Earth with ease. He even brilliantly gains the loyalty of the Free Jaffa movement by dealing with them in complete honesty. His only failing was to let his feelings for Qetesh override his common sense, resulting in her betraying and murdering him.
- Eddie in The Color of Money has this with his girlfriend, Carmen. He sees her as a Purity Sue, blinding himself to her Street Smarts and delinquent past. She's even wearing a necklace she stole from his mother, and he thinks it's just a coincidence.
- Zombieland: Columbus loves Wichita from the word go and insists on chasing her even though Wichita is a Jerkass con artist who stole his transport and weapon twice, on the first occasion leaving him for dead and on the second kidnapping him. This continues after she steals his vehicle for a third time to go to Pacific Playland with Little Rock, though on this occasion choosing to go after her ends up saving her life and it finally pays off with her returning his feelings.
- In Casino, Sam "Ace" Rothstein is known as a very intelligent and calculating man who is an ace at gambling, and is known to never lose. It's this reason he is put in charge of a big Casino in Vegas for the Mob. Everything is fine at first, until Sam falls in love with a woman hustler named Ginger, while he is watching her steal from a high stakes gambler. Despite this, and many bad signs and warnings from others, Sam marries her and quickly regrets it. He even gives her the only key to his saved fortune, which even makes the bank manager question it. It proves to be one of the reasons for the Casino's downfall. He only survives getting killed, because the Mob still feels they can use him to make money. Lampshades during the film.
Sam "Ace" Rothstien: "Before I married Ginger, I heard all the stories, but I didn't give a shit. "I'm Sam Rothstein", I said. I can change her."
- In Batman & Robin, Robin starts with just a crush on Poison Ivy, but her continued seductions of him, combined with her pheromones, soon make him fall blindingly in love with her and make numerous dumb decisions. Even after finding out Ivy is a villain he hardly puts up any resistants against her and completely believes her when she promises to help him and "turn over a new leaf" so they can be together. When Batman explains why Ivy has been trying to kiss them, Robin thinks he is just jealous that she loves him instead, and attacks Batman to defend her. He later sees a "robin-signal" in the sky and knows it is from Ivy, since she mentioned it while flirting with him, but just takes it as a sign of her love for him, not even questioning where or how she got it. This is ultimately subverted when he meets with Ivy in her lair. He pretends to still be in love with her and convinces her to share her plan with him as a sign of trust before sharing a kiss. Then he reveals he protected himself with rubber lips, negating her poison and proving her love to him was a lie. However, he does this while sitting right next to her, and she angrily shoves him into her lily pond to drown him for his treachery, officially "breaking up with him."
- Tragedy Girls: Jordan Welch is a levelheaded, supportive guy... who, unfortunately, has a massive crush on Sadie. While he's able to sense that something is wrong with McKayla, Sadie's best friend and partner in crime, he's completely blind to Sadie's true nature.
- In A Brother's Price, the oldest present sister Corelle has a crush on the neighbour boy and decided to pay him a visit - despite having been left in charge of the farm and her younger siblings. In the dangerous world where the story is set, this is a very dumb thing to do. The backstory also has a princess who is so in love with her pretty husband, that she excuses even his abusing her younger sister when he claims that the teenager "provoked" him.
- Pretty much the plot of the seventh book in the H.I.V.E. Series. Otto thinks that the reason Laura was acting strange around him was because he confessed his love to her and it didn't go well, but it was actually because she was being blackmailed by a member of the staff and her family was being held hostage. His lack of attention led to the death , injury or capture of 36 Alphas, and his own expulsion from the HIVE.
- This is parodied in Plague in the Gone series.
Virtue: "I'm going to refuse to do puberty. It makes you stupid."
- Older Than Steam, thanks to Francois Villon's The Great Testament:
Foolish love makes beasts of men:
It once caused Solomon to worship idols,
And Samson to lose his eyes.
That man is lucky who has nothing.
Wise men oft | into witless fools
- Older Than Print, actually note :
Are made by mighty love.
- Speaking of Samson, this is basically the best possible justification for the Idiot Plot of Samson and Delilah, considering that Delilah succeeded in getting Samson to tell her the secret of his strength after she'd already tried to exploit each version of the "secret" he'd told her three times before in order to hand him over to his enemies. It's also something of a testament to how charming she could be that the Philistines to whom she'd related these "secrets" the previous three times came back for one more try after her false information had previously gotten them thrashed—and they brought their money. Laugh as we might at his folly, the story's not so implausible to anyone who's seen the gullibility of a man thinking with the wrong head.
- This could be said for Daisy from The Great Gatsby, though she could simply be like that all the time.
- Even more so for Gatsby himself.
- He was never a main character, but Captain Typho, Padme's eyepatched guard in the second two prequels, fell in unrequited, unnoticed love with her, as revealed in the Star Wars Expanded Universe. After her death and funeral, he observed that she had died of being strangled, but there was no evidence of this on her skin, which meant the Force. Remembering that Anakin Skywalker had been scheduled as guarding her, he decided to track him down and hear the explanation, then either kill him or not depending on the answer. Keep in mind that this is after Order 66. He knows it's a long shot, and he knows that if Padme had known he was in love she would have urged him to let go and live his life, but he feels like he has to do this. Later he decides that Skywalker must have been killed, and Padme soon after, by a Sith, and he must find and kill this Sith - Darth Vader, specifically. The narration lampshades this once.
After all, no one in their right mind deliberately sought to make acquaintance of a Sith. But Captain Typho was not in his right mind. He was in love.
- Notably, while love gave him a goal both very difficult and quite suicidal, it didn't make him stupid. He was able to best the bounty hunter and Jedi killer Aurra Sing, stealing one of her lightsabers and clipping her biocomputer, though he did not kill her. He was cautious and planned, and was able to remember enough about the customs of different species that he could get plenty of information out of them. And he was even smart enough to acquire an obscure Power Nullifier for Force-users, knowing full well that a muggle can't beat a Sith Lord in a straight fight.
- In the Books of Pellinor, Hem repeatedly risks both his life and his mission to rescue Zelika because he loves her, even though he has no way of knowing whether she is even alive. As it turns out, she was killed soon after her capture.
- In the Dragonlance novels, Laurana's love for Tanis Half-Elven causes her to make the incredibly stupid decision to trust her Arch-Enemy Kitiara.
- Invoked in The Belgariad when Ce'Nedra asks Garion what's wrong with his friend Lelldorin. Lelldorin comes from the Arendish culture, known for Honor Before Reason, and Ce'Nedra comments that he's "so Arendish, he's practically incapacitated." Garion replies that Lelldorin is in love, and being in love makes some people's brains seem to leak out of their heads. Ce'Nedra, who just recently realized she's in love with Garion, is NOT pleased.
- Lazarus Long, in Time Enough for Love, has traveled back in time over two thousand years to visit his original family in 1917. What he doesn't count on is that, in doing so, he falls in love with his mother. This causes him to enlist in World War I to win her approval, despite having no personal stake in the war, knowing the outcome, and not knowing the future from his own personal point of view. He nearly dies as a result.
- In the story "The Warlock's Hairy Heart", seen in The Tales of Beedle the Bard, a fairy tale book for wizards and witches, the warlock believes that Love Makes You Dumb, so he performs dark magic to prevent this from happening to himself. It didn't end well.
- In Gene Stratton-Porter's The Song of the Cardinal, the young cardinal believes this even while envying the already mated birds.
As for the doves that were already brooding on the line fence beneath the maples, the Cardinal was torn between two opinions.
He was alone, he was love-sick, and he was holding the finest building location beside the shining river for his mate, and her slowness in coming made their devotion difficult to endure when he coveted a true love; but it seemed to the Cardinal that he never could so forget himself as to emulate the example of that dove lover. The dove had no dignity; he was so effusive he was a nuisance. He kept his dignified Quaker mate stuffed to discomfort; he clung to the side of the nest trying to help brood until he almost crowded her from the eggs. He pestered her with caresses and cooed over his love-song until every chipmunk on the line fence was familiar with his story. The Cardinal's temper was worn to such a fine edge that he darted at the dove one day and pulled a big tuft of feathers from his back. When he had returned to the sumac, he was compelled to admit that his anger lay quite as much in that he had no one to love as because the dove was disgustingly devoted.
- In Blood Promise, Viktoria Belikova falls for a casanova and is ready to be impregnated at age 17. When Rose rescues her, she accuses her of leading the casanova on and not understanding love.
- In City of Lost Souls, Jace has been Brainwashed by Sebastian, who is about to bring his Evil Plan to fruition. Jace manages to escape Sebastian's control temporarily, and wants to flee with the MacGuffin back to the Shadowhunters in order to prevent The End of the World as We Know It. However, afraid that the Shadowhunters will kill Jace to stop Sebastian, Clary keeps him from getting away, assuring that he ends up back under Sebastian's mind control and ultimately allowing Sebastian to advance his plan to the next stage.
- Harry Potter
- Alluded to in Harry Potter and the Half-Blood Prince, where said prince's notes in an old Potions textbook have allowed Harry to become top of the class. When he has to hide the book to protect his secret from Snape, his performance in class predictably drops; Potions master Professor Slughorn, however, sees nothing odd in this, as it starts shortly after Harry begins dating Ginny Weasley.
- While he was a firm believer in The Power of Love, Albus Dumbledore was not blind to its downsides, having experienced that firsthand. The first and only person Dumbledore ever loved was the future Dark Lord Gellert Grindelwald. His love for Grindelwald was so strong that it blinded him to the man's many faults, which eventually led to the death of his sister and the estrangement between Dumbledore and his brother. Unsurprisingly, Dumbledore swore off falling in love ever again for exactly this reason.
- In Heart of Steel, falling in love with Julia makes Alistair neglect things like sleep and his plans for world conquest in his pursuit of her. Unfortunately, sleep deprivation leaves him mentally weakened, and vulnerable for the moment when Jim finally wrestles free of his controls.
- A variation in Misery, as the love in question is a fan's love for a fictional character. Annie is insane and lets her love of the fictional Victorian airhead Misery Chastain cloud her judgement, and Paul is eventually able to exploit this to kill her.
- Kate from Lost started out as one of the main characters in the ensemble, a fairly solid example of a Troubled, but Cute girl. However, as the series entered its second season, she became increasingly obsessed with Jack. Her attempts to rescue/ingratiate herself with/impress or otherwise have contact with him have led to an ever-growing list of problems that are completely her making—she seems to think she's back on a junior high playground (albeit one where she gets to have sex with Sawyer, the Jerk with a Heart of Gold, before going back to see what Jack is up to), not trapped on an island with a group of psychotics and a bunch of Epileptic Trees.
- This is taken to new lows in the season 5 finale, when a group of Losties ends up in the past thanks to some pesky time-travel, and they have to decide whether or not to detonate a nuclear bomb, whose explosion might change the future and prevent everything they've gone through to happen. Jack finally admits that his main reason to do it is that he lost Kate's love. Juliet's reason is that she noticed Sawyer, her current love interest, looking at Kate in a certain way. Kate and Sawyer go along with the plan. Sadly, Miles and Hurley reluctantly agree instead of pumping these emo douchebags full of hot lead.
- Damon's love for Elena or Katherine in The Vampire Diaries means he fits this trope as well as Love Redeems, Love Makes You Crazy, and Love Makes You Evil, which he has also played with at some point during the show.
- Klaus can fit too, as he has been manipulated by Caroline a couple of times after developing a feelings for her.
- And as of season 5, Katherine, who decided to stay in town instead of running away with Nadia after stealing Elena's body, all because she wanted to woo Stefan.
- Ianto's love for his girlfriend in Torchwood leads him to hide her in the basement of a heavily armored and base filled with alien tech. She's a half-converted evil cyborg woman. He then proceeds to date the guy who kills her.
- And Tosh secretly bringing her secret alien girlfriend to work, despite her suspicious resemblance to a serial killer on the loose. And the questionable security movements made by Gwen and Jack for Rhys and John respectively.
- In Smallville, this is a continually growing problem with Clark to the point that, in the first half of Season 8, he was finally starting to act a little bit like Superman until Lana returned at which point he lost about 7 years of character development.
- A smaller example: Chloe Sullivan, gets dumb when she is romantically involved with Ian, Jimmy and Davis. Also makes her into a Horrible Judge of Character for the first and third occasions.
- Pushing Daisies has this as a main element, in a subtle way... until "Water and Power", when the anvil is dropped on Emerson Cod's foot. The Narrator even points this out.
- Nobody, least of all the writer responsible, has any idea why Marian, in the 2006 BBC version of Robin Hood ran up to Guy of Gisbourne, an unhinged man who was obsessed with her, and began yelling: "I love Robin Hood! I'm going to marry Robin Hood!" Guy responded by running her through with a whopping great sword.
- Wilson references this in season 4 of House after House thinks that his attraction to a female doctor is interfering with his diagnostic skills.
"Boy meets girl, boy gets stupid, boy and girl live stupidly ever after."
- There also was an indirect, but very literal version in the episode where the patient of the week was a former prodigy and teen genius, now working as a FedEx deliveryman. Turns out that he'd fallen in love with a girl who had maybe 1/3 of his IQ, and started habitually using a drug made from a combination of prescription-strength cough-syrup and strong alcohol (known as 'Astro-Tripping' or 'Blue Drank') to slow his mind down to the point where he could relate to her. Of course, using something like that on a daily basis for years can take its toll...
- Suzy Pepper of Glee had a crush on her teacher, called him at 3 a.m., gave him a tie with red peppers so when he wears it he can think of her. Teacher rejected her, she ate world's HOTTEST PEPPER, burned holes in her esophagus, and got put in a medically induced coma for 3 days. To add insult to injury, the teacher then added that girls are so fragile.
- Lister references this in Red Dwarf:
It's really debilitating, being nuts about someone. You lose twenty I.Q. points every time you talk to them.
- Played with in Frasier, where Frasier is constantly doing face-palmingly stupid things whenever he gets into a relationship with a woman and directly ignoring his very own psychiatric advice...and he knows it, and can't help it, and constantly hopes his romantic plans won't blow up in his face this time, no matter how many times his Genre Savvy little brother reminds him how badly he suffers from this trope, with his stupidity probably reaching a zenith in "Don Juan in Hell". This is just one aspect of pretty much the very core of Frasier's character being brilliant at giving other people advice, and terrible at following it himself.
- On Gilmore Girls, Lane is so smitten with a boy that she pets his hair when he's turned around, then runs away, embarrassed. She winds up turning to Lorelai for advice, who advises her that when it comes to love, "it pretty much all comes out in stupid."
- Sherlock states this outright in A Scandal In Belgravia. It is directed at Irene Adler who has just finished tearing into him about his apparent asexuality, something repeated throughout the episode.
I've always assumed that love is a dangerous disadvantage. Thank you for the final proof.
- Game of Thrones:
- King Robb Stark falls in love with Talisa Maegyr and marries her, despite having already promised to marry Lord Walder Frey's daughter. His mother warns him what a stupid political move this is but he marries her anyway, which doesn't only make him lose an important ally, but also gets him, his wife, his mother and most of the Northern army killed when the Freys murder them during the reconciliation wedding in Season 3, where he doesn't even realize how dumb it is to parade his new wife in front of his supposed-to-be-wife, not to mention supposed-to-be-father-in-law. In the books, Catelyn forbade him to bring Jeyne to the Twins for this very reason. Lord Karstark remarks that Robb lost the ongoing war the day he married Talisa. This is in contrast to the books, where he marries Jeyne Westerling out of a sense of honor (and hopes the Freys will understand). The context makes Robb seem more brash and impulsive than his book counterpart, who already got some criticism; no less than Tyrion Lannister was heard to observe, "Better to leave her with a bastard in her belly," after hearing of his folly with Jeyne.
- Catelyn frees the Kingslayer behind her son's back in an attempt to get her daughters back.
- Sansa is convinced that Joffrey is a great guy until he chops off Ned's head.
- Jaime Lannister has some shades of this in his relationship with Cersei. He's not blind to her faults or her evil actions, but he genuinely believes that she is acting for the greater good of their family and that she ultimately wants to build a better world. He eventually realises what a terrible person she is when she decides to let Daenerys and Jon be slaughtered by the White Walkers after promising to help.
- Dawson from Dawson's Creek was an example of this from time to time, but averted it a lot early on. While watching a film noir with Pacey, Dawson couldn't figure out why the detective was so oblivious to the fact that the girl setting him up.
- Friends: Monica and Chandler when they first develop feelings for each other. Also Rachel when she has a crush on Joshua in season 4.
- Star Trek: Deep Space Nine:
- Odo becomes smitten with the Female Changeling during the occupation of Deep Space Nine in "Behind the Lines" and "Favor the Bold." He becomes so absorbed in linking with her that he neglects his duties. He became involved with her despite full knowledge of the Dominion's tyranny and the Female Changeling's prior antics. Fortunately, he snaps out of it upon realizing what the Female Changeling and the Dominion have in mind for the Alpha Quadrant.
- Rom's backstory contains an example of this. So smitten with Nog's mother was he that he didn't even skim the Ferengi marriage contract. Which ended with him getting cleaned out by his now ex-wife and left alone with Nog.
- Scandal: Poor Huck. He wanted to believe that his girlfriend Becky was the best thing in the world. But he discovers that she not only shot the President, but set him to be the fall guy. She actually wanted him to come with her, and he was torn over what to do. The good news is that he did the right thing, which was to try to take her down. The bad news is that she caught wind of his attempt, and not only got away, but even murdered the entire family that he keeps an eye on!
- White Collar: Neal Caffrey is generally pretty intelligent. He can always come up with a good plan, and can often get exactly what he wants out of a situation. But his love for Kate has resulted in him making some remarkably idiotic decisions - walking right into a trap that ended with him going to jail and breaking out of jail only a few months away from the end of his sentence stand out as some of the most egregious examples.
- From The Cosby Show, the vast major of incidents involving Vanessa Huxtable getting in trouble usually start as a result of her boy-craziness.
- Mentioned in Castle, shortly after Alexis and Pi break up:
Alexis: All those things my dad said when I was moving out, about me making a mistake moving in with my boyfriend, he was right. I can see it so clearly now. Why didn't I then?
Beckett: You were in the love haze.
Alexis: The love haze?
Beckett: It's like a drug. It makes intelligent people do... stupid things. And then it clears and you look around and you wonder "What was I thinking?"
- While Buffy the Vampire Slayer mostly averts this, the Buffy/Angel romance was definitely this at times, particularly from Buffy's standpoint. While it's slightly justified by her being young, she still crossed this line. How about choosing to get back together with Angel despite knowing it's a bad idea (he'll lose his soul and turn evil if she sleeps with him) and him saying to her face that he wants her so badly he's willing to lose his soul again just so he can sleep with her. When you ex tells you that, you don't get back together with them. It's a marked indicator of her Character Development when Angel returns again just before the series finale, and she admits that she doesn't know what she wants and still needs to finish figuring herself out, before sending him off to return to Los Angeles while she metaphorically and literally deals with her own problems.
Xander: Buffy, I still love her.
- Discussed in Season 7 when Xander objects to Buffy planning to kill Anya, despite the fact that Anya brutally murdered several humans; Buffy herself believes that Xander's lingering feelings for Anya are clouding his judgement:
Buffy: I know. And that's why you can't see this for what it really is.
- Doctor Who: The Doctor repeatedly invokes the rules of time travel, No. 1 being you can't go back and change fixed points in time or otherwise alter major historical events. But in the Series 9 finale "Hell Bent", he decides to break all the laws of time in order to prevent Clara Oswald from being Killed Off for Real after that already happened, an act that threatens to destroy the space-time continuum.
- In Series 10's "The Pyramid at the End of the World", Bill Potts is so desperate to save the blind Doctor from dying in a lab explosion (he cannot unlock the door unless he can see the numbers on the lock) that she consents to humanity being conquered by the Monks against his wishes. It should be noted that it is not romantic love she feels for him, as she is a lesbian; she loves him as a grandfather figure and extremely close friend. (She also believes it will allow him to be able to fix the consequences of her act.)
- From Black Flag's Anti-Love Song rewrite of the Kingsmen's "Louie Louie":
"This pain in my heart
It just means I'm not very smart
Who needs love when you've got a gun?
Who needs love to have any fun?"
- "Everybody Plays The Fool" by The Main Ingredient is all about this trope.
- "Herp de Derp" by Gregory Brothers is this combined with Gibberish of Love:
Herp herp herp herp herp de derp
I'm not this awkward all the time
Only when love is on the line
Herp de derp de derp de derp de derp derp derpy
- Talking Heads' "Uh-Oh, Love Comes to Town" (from Talking Heads: 77) is all about love messing with your head and causing bad decisions.
Jet pilot gone out of control, ship captain on the ground
Stock broker make a bad investment when love has come to town
- Daniel Amos' "I Love You #19" (from Horrendous Disc) briefly touches on this.
Now if I said it real pretty in a pretty rhyme
Does your mind get cloudy that's a dirty crime
- In Pathfinder, divine spellcasters with the Lust domain gain Touch of Idiocy and Confusion to their domain spell lists, becoming able to inflict this trope on enemies.
- In The Good Person of Szechwan, Shen Te is on the verge of sorting out her problems when she meets Yang Sun and falls in love, and common sense goes out the window. Even when she learns beyond any doubt that he doesn't love her and is just stringing her along for his own advantage, and even though their relationship keeps ruining things for her every time her life looks like it might be taking a turn for the better, she's so lovestruck she can't bring herself to give him up.
- One common interpretation of Shakespeare's Romeo and Juliet has this trope as its lifeblood.
- And in a similar vein, Antony and Cleopatra.
- In the vein of "jealousy makes you dumb" in Tosca. By all means, if the villain who's openly ogling you hints that your lover might be cheating, it's bound to be true!
- Baldur's Gate features Viconia, a Neutral Evil Drow Cleric on the run from her equally evil race. Then the Player Character saves her a few times, worms his way into her dark heart, and if he plays his cards right, he can change her alignment to True Neutral... which disqualifies her from using a powerful, one-of-a-kind holy symbol dedicated to her (still evil) goddess.
- The whole plot of the sequel is essentially caused by the elven queen Ellisime sparing a villain's life out of love, exiling him instead (and doing nothing about his High Mage powers). At the end of the game she publicly admits her mistake, though.
- The title character of Max Payne in the second installment probably qualifies. He repeatedly notes that his feelings for Mona are driving him into one mess after another.
- In Pokémon, this is what happens if a Pokemon is hit with the move Attract from a Pokemon of the opposite gender, or if the attacking Pokemon uses a move that require physical contact (e.g. Tackle) onto a Pokemon of the opposite gender with the Cute Charm ability (though it works only 30% of the time in this case).
- Played heartbreakingly in Prince of Persia (2008). Magical waif Elika sacrifices herself to reseal the Big Bad Ahriman back into his can. The Prince, up to this point a cynical Jerkass loner with a smarmy comment for everything, is left lost. So he decides to destroy Ahriman's seal and bring both of them back into the world again, screwing over the entire world. The expanded epilogue tries to rationalise his choice by suggesting he wanted to bring Elika back so she could help him find a more permanent solution; leaving them both sealed is just playing the waiting game until somehow Ahriman is unsealed again and then the Prince (or someone else) would have to find a way to beat him without Elika's powers. Too bad Elika doesn't buy his justification one bit, she despises him and never forgives him, in the end leaving him for good.
- Luisa Fortuna of Red Dead Redemption is shown to be deeply in love with Rebel Leader Abraham Reyes, a man who can barely remember her name and is clearly a power-hungry egomaniac. She even goes so far as to try and attack armed soldiers with a knife in an attempt to rescue him.
- In Theresia: Dear Emile, Hot Scientist Maylee says this word-for-word after she has sex with the main character of the Dear Martel story.
- In Persona 3 FES, near the climax of The Answer, Yukari's character is completely derailed in a way that makes no sense due to her love for the protagonist. She selfishly wants to use the chance to she has to go back to the moment the MC sacrificed himself and stop him from doing it, regardless that this will definitely cause Nyx to return and destroy the world. This creates a Conflict Ball that results in SEES fighting one another and nearly ending their friendships.
- Selvaria in Valkyria Chronicles. She's utterly devoted to Maximillian, but she doesn't realize he doesn't return her feelings until he sends her to use a Suicide Attack, showing once and for all that he doesn't give half a damn about her personally. You'd think that'd be a bad move on Max's part, considering that Selvaria could turn him into a McNugget combo with less effort than it takes for her to get dressed in the morning, plus she's developed a tenuous rapport with her counterpart on the good guys' side and could probably defect to their side. But no. She goes ahead and blows herself up, tearfully praising Max's name, but makes a point of betraying him at the last second by sparing the only people in the Gallian military capable of stopping him.
- In Dark Souls II King Vendrick's love for Queen Nashandra causes him to make one foolish decision after another, from waging war against the Giants to numerous failed attempts at curing the Undead Curse, distracting him enough for Nashandra to take the throne from under his nose. This trope pretty much sets the entire plot in motion. Even worse, after he figures everything out, he's STILL in love with her!
- Later games in The Elder Scrolls series reveal this to have been the case for Arena Big Bad, Jagar Tharn. Tharn, who had successfully secretly usurped the Imperial Throne, had a major attraction to the Dunmeri Queen Barenziah, who took advantage in order to assist those working to bring him down by deciphering his notes in order to find the pieces of the Staff of Chaos.
- Nine Hours, Nine Persons, Nine Doors: Junpei and Akane are reasonably intelligent people, except when they're around each other. Maybe that's why Akane abandoned him when she went off to save the world from Radical-6. This trope is a major plot point in Akane's backstory, where it nearly gets her killed and then saves her life.
- Phoenix Wright from Ace Attorney is generally inteligent in his own way, but in a backstory case he absolutely refuses to believe that his girlfriend might not be who she thinks he is, despite all the evidence that she was using him, even when Mia had shown that Dahlia wanted to kill him, going so far as to declare that "Dollie" who testified against him during his trial was somehow a fake. And he was right. The girl he was dating at the time was not Dahlia but her twin sister Iris, who really was as nice as he claimed her to be. Although he himself didn't know it until much later.
- Girl Genius:
- This exchange.
- Lampshaded as Gil is fighting Captain Vole:
- Tarvek himself acquires fumbled speech on the subject and generally doesn't fare much better:
Violetta: You are joking! I really have to explain this to you? You live for this stuff! Argh! It must be love.
- Also implied to have happened to Bill Heterodyne in regards to Lucrezia. He was insistent that she could join the "good guys" despite blatant and constant evidence to the contrary.
- Then there was Moloch von Zinzer, whose cooking would invariably go from "acceptable" to "boiled sponge with gravy" immediately after serving Sanaa.
- In her very first appearance, Susan in El Goonish Shive declared this trope. That said, the comic has not supported her view.
- Sandra and Woo nails it.
- Matt from Hodges Pond still loves Trixie despite the fact she put him in a 3 week coma.
- This hit Marion of Sunstone hard; being new to the type of relationship she was sharing with Alan caused her to discard her better judgement in favor of doing everything she could to take things further, leading to her neglecting the safety aspects integral to BDSM. This does not end well.
- Ally&Lisa aren't exempt from this either. It's the main reason they rush into moving with each other just three weeks after meeting in person.
- A Day With Bowser Jr: In Rise of Fawful (part 1), Bowser Jr crush on Kylie renders him oblivious to Fawful's obvious ploy to extract secret information from him.
- Snap from ChalkZone goes stupid every time Queen Rabsheeba shows up. Usually stuff like eating his magazine, turning into dust, etc.
- The Grim Adventures of Billy & Mandy makes fun of this trope. In the movie "Big Boogey Adventure", Grim and Billy have this conversation referring to Irwin's big fight scene.
- Referenced in Futurama, although the circumstances and Fry's general level of intelligence stop it being an example.
The Worm King: He's bluffing! No creature would willingly make an idiot out of itself!
Fry: Obviously you've never been in love!
- Non-romantic example: In the My Little Pony: Friendship Is Magic episode Twilights Kingdom Part 2, after experiencing Fluttershy's friendship, Discord is so eager to have Tirek for a friend that he becomes Genre Blind to the possibility that Tirek would double-cross him.
- South Park: In "The Succubus", the typically Genre Savvy Chef falls for a succubus, who has this effect on him, albeit via More Than Mind Control on her part. It takes the boys exposing her to get him back to reality.
- Rodney from Total Drama is an extreme parody of this trope. Every single time he attempts to talk to a female character he just ends up muttering incoherent gibberish.
- Mr. Cat is the smartest of all the characters on Kaeloo, but he does some pretty idiotic things to get the attention of his crush Kaeloo.
- In Miraculous Ladybug, many of Marinette's worst decisions are driven by her unrequited crush on Adrien, especially in Season 1. This includes wasting a Lucky Charm to try and keep Chloe away from him, stealing his phone to erase an embarrassing voice mail, and verbally tearing down Lila after she starts putting the moves on him.
- Truth in Television, maybe? This article claims it is.
- Everyone in this Cracked article: "The 6 Biggest Over-Achievements in the History of Marriage". From entry #6:
Why was [the Earl of Snowdon] so full of himself that he took marrying a princess for granted? Some say ego, some blame Margaret, but his prep school classmates probably have the real answer here: He had a monster dong. And that lets you get away with anything.
- While it might be a better example of Lust Makes You Dumb instead of love, people who live in more rural areas will tell you that you're most likely to hit a wild animal crossing the road during the spring. Since spring is mating season when most female mammals go into heat, it would start to appear that the idea of mating starts to override an animal's basic common sense and self-preservation.
- Steve Irwin's account of the first time he saw his future wife Terri was that he was so lovestruck that he nearly got eaten by the crocodile he was feeding at the time.
- The Japanese kanji 惚 can be translated as both "fall in love with" and "grow senile".