Everyone knows when you see two dogs tearing into each other, the last thing you should do is try to get between them. What some don't realise is that the same can be true of people, too.
This trope is when two characters in the middle of a bitter argument make up their differences over a common love of abusing someone else — usually the first person who intervenes to get them to make up. They'll tend to start out with grudging Dumbass Has a Point and Actually Pretty Funny's, before really warming to the tag-team beatdown.
Can cross over with Truth-Telling Session.
Subtrope of No Good Deed Goes Unpunished, and related to Unwanted Assistance and Contempt Crossfire. Inversion of Apple of Discord, when a third party makes two allies start arguing - this is about making two arguers temporarily join forces against the intruder. Compare/contrast Enemy Mine, when two mortal enemies join forces to defeat a mutual threat and Genghis Gambit (where the mediator deliberately invokes this).
- As Revy and Roberta are beating the nine hells out of each other in Black Lagoon, Rock gets the bright idea to try to get them to talk about their problems. Being as both of them are in full-on violent mode, the response from the two is unsurprising:
Revy and Roberta: (simultaneously) STAY THE FUCK OUT OF THIS!
- Ranma ½: When Gosunkugi gets ahold of paper dolls capable of controlling anyone he wishes, he tries to use this opportunity to win Akane's heart. Unfortunately, after he test-drives a few of his dolls on Ranma to see if they actually work, Ranma's suspicions are raised to the point where he openly confronts him about it. Akane immediately rushes to Gosunkugi's defence and our two opposing sides begin to bicker.
Ranma: How come you're bein' so stupid, stupid?!
Akane: Speaking of stupid, look in a mirror!
Gosunkugi: Um, Akane? Ranma? Please calm down. I haven't put the doll on, so can you not fight until I—
(both Ranma and Akane send him airborne)
Ranma: You stay outta this!
Akane: This is between me and Ranma!
- In the Azumanga Daioh comic strip, Sakaki once sees two cats about to fight. She instantly rushes in to stop them, but since the affection is pretty much one-sided on Sakaki's part, they both settle for chomping her hands instead.
- This is a pretty common fate for anyone who steps in between Ryoko and Ayeka. The biggest one comes towards Tsunami, who finds her explanation about herself and Sasami interrupted because the two are more worried that Tsunami is gonna be Sasami in the future and when she tries to get their attention, they both tell her to shut up!
- In the Pokémon episode "Showdown at Dark City," Ash and his friends decide to break up a gang war between rival gyms that's destroying the titular city. After he gives them "The Reason You Suck" Speech, the leaders of both gyms bury the hatchet—and decide to attack Ash. Good thing Nurse Joy was there to save the day.
- In one Dork Tower/Shop Keep strip in Dragon, Bill is tired of the wargamers, roleplayers, boardgamers and cardgamers calling each other "freak" and "weirdo", and explains to them all that they can all get on, as illustrated by the fact he enjoys playing all those games. The entire shop concludes that he's a freak and weirdo.
- In an early Doonesbury comic strip, activist Mark Slackmeyer tries to quiet down an unruly crowd of disorganized and divided protesters by having them unite under a common goal, and they end up shouting "KILL THE MODERATOR!"
- One Peanuts strip◊ sees an exchange of snowballs over Snoopy's dog house while he's lying on it. He stands up and gently cautions, "peace." Cue a hail of snowballs striking him from both sides.
- One Garfield strip had Garfield and Odie facing each other, ready to fight, when Jon comes in and tells them that they should get along by focusing on something they have in common. They face Jon and angrily leer at him.
- Overlaps with Neutrality Backlash in The Last Son. Thousands of years ago, the Kryptonians came across the Kree-Skrull conflict, and attempted to mediate between them to end it peacefully. Neither side wanted to yield, and instead they tried to sway the Kryptonians to their side, so they ultimately gave up and abandoned the conflict altogether. It's partially subverted because, when the Kree and Skrulls tried to destroy Krypton in revenge, they were utterly decimated by their Battlestation Sentrius.
- Implicitly defied by Ash in Chapter 16 of Pokémon Reset Bloodlines. He overhears Misty and Iris having an argument about clothes, and decides not to get between them presumably for fear of this happening.
- In the Robert Asprin book The Sweet Myth-tery of Life, Guido describes this as an inevitable result of getting involved in a domestic dispute. As previously shown by Skeeve in Hit or Myth, when he got the reluctantly married king and queen to get along by telling off both of them. (And wisely brought bodyguards when he did it.)
- In Dresden Files, Harry tries to defuse what's about to go down between Ebenezer McCoy and Jaren Kincaid. He ends up with a gun pointed at his face and his spine.
- Discussed and defied by the Feegles in I Shall Wear Midnight - "Any man who interferes with the arguin' of women is gonnae find himself with both of them jumpin' up and doon on him in a matter of seconds".
- Invoked by Phule in the first Phule's Company book, where he tells his feuding lieutenants to find common ground "even if it's just what an unreasonable son-of-a-bitch your commanding officer is".
- The Bible (Proverbs 26:17) — "Like one who grabs a stray dog by the ears is someone who rushes into a quarrel not their own."
- In Black Books, Bernard and Mannie take time out from an argument to insult Fran, and end up resolving their own differences in the process. Until Fran leaves the room, at which point things go back to normal.
- After J.D. intervenes in an argument between Dr. Cox and Jordan;
J.D.: And just like that all the hatred they had for each other was instantly directed at me.
- In a Cold Open, J.D. gets an earful from Carla and Elliot after commenting on their argument. When he realizes what he's gotten into, an Imagine Spot shows him pulling a lever that rewinds time to before he to involved. He makes the same commments and gets roped in again.
- After J.D. intervenes in an argument between Dr. Cox and Jordan;
- In the Xena: Warrior Princess episode "Been There, Done That", Joxer attempts to invoke this trope in order to stop the feuding families. He gets a couple dozen arrows to his face for his trouble (but again, this being a "Groundhog Day" Loop, he gets better).
- Played with on Frasier; Frasier sits Roz and Julia down in the cafe to try to get them to make nice, and when they find common ground insulting him, he graciously leaves them to it. The moment he's gone, though, they both get up to leave, and are bickering again before they reach the door.
- In the Malcolm in the Middle episode where Grandma Ida loses a leg after saving Dewey, one of her grandsons, from being run over by a truck, Lois forces her oldest son, Francis, to take care of Ida until she fully recovers, citing that since he's unemployed at the time he has plenty of time to do so. Francis tells Lois that's a terrible idea because of how much they hate each other, but Lois responds that she doesn't care what it takes for them to get along but he's going to stay with Ida no matter what. When Francis starts pointing out Lois' flaws, Ida adds several other flaws that she's noticed while raising her.
- In the Friends episode "The One With The Racecar Bed", Ross' attempts to endear himself to Rachel's father (who already didn't like Ross before he found out he'd gotten Rachel pregnant out of wedlock) aren't going well. Rachel's attempts to get them to try and warm up to each other segue into a conversation about Rachel's "specialty" chiropractor, and the two soon find common ground... criticizing Rachel's questionable life choices.
Ross: Wow, this is going so well! Did ya see us? Did ya see?
Rachel: (miffed) Yeah, honey, I was standing right there. Why don't you just tell him about the mole I haven't gotten checked yet?
Ross: ...Excellent! (walks off)
- In the Mutants & Masterminds forum, one post about a crossover setting notices that between the Fandom "Odds and Ends of the Freedomverse" and Fires of War for The Algernon Files, there are two incompatible Golden Age heroes with a connection to the Count of Cagliostro. According to the post, supporters of both heroes in-universe claim the other one was lying:
At which point the conversation gets much, much less civil, and some folks try to smooth the waters by noting that as neither was exactly a shining figure of honesty, so really, we can never be sure that either of them was telling the truth, so it's silly to argue.
This statement usually goes over far less well than they imagined it would, and generally ends with everyone going home in a foul mood.
- This trope, along with The Masochism Tango, is the entire point of the Edward Albee play Who's Afraid of Virginia Woolf?. George and Martha attack each other at every turn, but take more delight in ganging up to tear apart the innocent young couple they invite round for drinks, (lots and lots of drinks). It's heavily implied they do this all the time to keep from killing each other.
- West Side Story: Tony's attempt to break up the rumble between the Jets and Sharks at Maria's request only serves to raise everyone's tempers, until the situation devolves from what could have been a begrudgingly-honorable, non-lethal fistfight to a knife fight that leaves both Bernardo and Riff dead and sets of the tragic chain reaction of the final act.
- Simon Munnery's character Alan Parker, Urban Warrior, told a story about how he found himself in a pub in Glasgow and witnessed an argument between two men, fans of bitter rivals Rangers and Celtic. Alan stepped in, telling them that they shouldn't be fighting each other, but instead unite against the capitalist oppressors. He then took their scarves off them, tore them in half and then tied them back together so that they now read "Celgers" and "Rangtic". And do you know what those men did? They attacked him: Together! To be clear, Alan considered this a success.
- In The Class Menagerie, Tony at one point tries to get his best friend Kevin and his roommate Brad to stop flinging Your Mom jokes at each other by pointing out that neither of them even likes their mothers. They promptly switch to flinging "your roommate" jokes and "your best friend" jokes (respectively) at each other instead. (which is admittedly a sort of stealth compliment, but Tony still clearly wishes that he'd never gotten involved)
- In the Arthur, King of Time and Space version of the scene in Arthurian myth where Sir Beloberis de Ganis gets between Lamorak and Meliagrant, who are dueling over whether Morguase or Guenevere is fairer, pointing out that any knight would consider his own love to be the fairest, they both take this as an insult and turn their lances towards him.
- Ménage à 3: When Sonya and Yuki are fighting over which one should get to be Gary's girlfriend, Gary's suggestion of "both" instantly redirects their anger towards each other at him.
- Flame Warriors' typically verbose description of forum users has this to say about the archetype they call Diplomat:
Diplomat butts into hot disputes, presuming that the combatants will welcome and appreciate his even-handed and eminently reasonable mediation. Frankly, he gets what he deserves.
- Invoked by ED-tan in this user-created Gaia Online comic episode.
- In Family Guy, Peter is upset that he can't find way to bond with Stewie, until he discovers that beating up Lois is the perfect way to do it. Crosses the Line Twice when they lock her in the trunk of a car and sink it in a lake.
- On The Simpsons when Marge went after Itchy and Scratchy, the series staff did an episode where a squirrel character based on Marge tries to stop a fight, but the duo decides to knock her head off instead. Given that the only other time they've worked together against someone else was an old wartime special where they beat up Hitler...
- Zig Zagged in the My Little Pony Friendship Is Magic episode "Over A Barrel": Pinkie Pie tries to settle tensions between the settlers and the buffalo with a song-and-dance number. They briefly agree... that it's the worst song they've ever heard... and then go back to fighting. Later, just as the buffalo are about to give up their stampede, she reprises it... and they decide to go through with the stampede as a result.
- In the Spongebob Squarepants episode "The Other Patty", Mr. Krabs and Plankton grudgingly team up to try and steal a new competitor's secret formula. Throughout the episode, the two spend their time disagreeing and bickering with each other. It's eventually revealed that SpongeBob started the competing restaurant to help Krabs and Plankton's friendship. The two respond by chasing after him, with intent to beat him up.
- Witness any police intervention in a domestic argument. (Or anybody else's, of course, but the police are the only ones professionally obliged to stick their heads over the parapet.) What they tend to really hate about such jobs is that even when one partner is clearly being abused, they'll often firmly take their abuser's side.
- This can happen on many internet forums. Trying to end a Flame War between two or even more users will result in them to take out their frustration on you with heaping insults. Considering that it's the internet, this is no surprise at all.
- This can be particularly amplified when it comes to political, religious, and ideological disputes. Those who take the "centrist/moderate" position often fall victim to this trope.
- Both The News Quiz and Private Eye pointed out that William Hague made it his mission to unite the factions of the Conservative party and succeeded; Margaret Thatcher and Edward Heath both hated him.