Given that the series revolves around organized crime, it was too obvious that Grand Theft Auto was going to get its own page of this trope.
3D Universe
- Grand Theft Auto III:
- Catalina crosses this when she shoots Claude, her own boyfriend. Later, in the final mission, she betrays him again and kills Asuka and Miguel.
- Salvatore crosses it in "Last Requests" when he sends Claude on a mission with the intention to kill him after Salvatore finds out that Maria was having an affair with him.
- Grand Theft Auto: Vice City:
- Ricardo Diaz crosses this in the mission "Death Row", admitting to Lance Vance that it was he who killed Lance's brother and then sending Lance off to be tortured to death.
- Sonny Forelli crossed this before the game's events. In the final mission, it is revealed that he set up the entire incident which landed Tommy in jail, with no explanation for why he did that being given. This shows that he has no problem betraying his close friend and one of his most powerful men in his organization for no reason and shows no remorse for this. And it is likely that Sonny would have killed Tommy if he had given the money he made from his empire's operations.
- Lance Vance seems to really cross this when he allied with Sonny and tries to kill Tommy. He doesn't even show remorse when he tries to kill Tommy, and you see that he does it with glee. For what it's worth, he was delusional enough to think that he was pulling the weight when he and Tommy were working together.
- Grand Theft Auto Advance:
- Vinnie crosses it when it's revealed that he was the one who was behind Jonnie's and Cisco's deaths and also faked his own death, all because he didn't want to share money with Mike.
- Grand Theft Auto: San Andreas:
- Tenpenny's actions — When he was under investigation for various crimes, he instigated the attempted murder of Carl Johnson's brother Sweet, that leads to their mother's death. He also has his protege kill a police officer who was investigating him, and uses said death to blackmail Carl into destroying evidence, kill witnesses to his crimes, and kill those investigating him. He attempts to kill people who work for him when they are useless to him.
- If Pulaski didn't already cross it by killing Hernandez and trying to kill CJ, he most certainly crossed it during the chase when he not only jokes about trying to rape his sister and spying on her and her boyfriend making love, he even insults his mom by making fun of her face after she was gunned down and gleefully joking about the other guys screwing around with her corpse! The head stomp he received from CJ after being badly wounded was EXTREMELY satisfying.
- OG Loc crosses it when he ordered CJ to kidnap and kill the manager of Madd Dogg (which also resulted in the death of an innocent woman alongside the manager), and as if that were not enough, also ordered him to kill all his guards and steal the rhyme book of Madd Dogg to be made famous. Not only that, but when Smoke betrays Carl, Sweet, and the rest of the Grove Street Families, OG Loc sides with Smoke in hopes of becoming famous in spite of his lack of talent. To make things worse this drives Madd Dogg into depression and almost makes him commit suicide... with people even encouraging him to jump!.
- Catalina shooting civilians randomly... just because she enjoys it. Even CJ himself was disgusted. Later, she also rapes CJ many times.
- Grand Theft Auto: Liberty City Stories:
- Paulie Sindacco intersects the horizon with the attempted murder of Salvatore, sending his henchmen to take him to the crusher.
- Toni's mother has probably crossed the line with the attempted murder of her own son for not being "man enough".
- If there was a point where Donald Love had crossed the line, it was when he planned and executed the bombing of the Fort Staunton city district, killing hundreds of innocent people, just so he can earn a buck over its redevelopment.
- Massimo Torini crosses it by starting gang wars to prepare Liberty City for the Sicilian mafia invasion.
- Grand Theft Auto: Vice City Stories:
- Marty Jay Williams crosses the line when he kidnaps his own wife Louise and tries to turn her into a prostitute.
- Jerry Martinez crosses this when he kidnaps, rapes, and intentionally injures Louise.
- Armando Mendez absolutely crosses this when he kidnaps and (presumably) tortures Louise. She dies as a result.
HD Universe
- Grand Theft Auto IV: For obvious reasons, this trope is a key theme in the storyline. Niko Bellic himself refuses to seek redemption in large part because he considers himself to have crossed the Moral Event Horizon long ago. ("Life is complicated. I've killed people, smuggled people, sold people.") Given his actions, human trafficking could be a good candidate for this. At the end, however, he is able to realize that there may be a better option for him.
- Playboy X ordering Niko to kill Dwayne, his own friend and mentor.
- Dimitri Rascalov. For most players, it will come when he sells Niko out to Bulgarin, when he kidnaps Roman, or when he kills Roman in the Deal ending. By the end of the game, he's definitely on the far side. However, an interpretation is that he thought he'd crossed it after he had you kill his best friend and boss, Mikhail Faustin. After this, he just goes completely Ax-Crazy and starts betraying and killing everyone.
- Francis McReary when he orders Niko to kill his brother Derrick to protect his corrupt career. Then again, Derrick asks you to do the same to Francis, but he's convinced that Francis is gonna hire someone to do it to him first...
- Some players consider Aiden O'Malley's death one for Derrick himself, especially when it turns that he really did betray him and Bucky Sligo.
- In "That Special Someone", it is revealed that Darko Brevic (Niko's former friend and comrade) crossed it when he betrayed his own squad in the Yugoslav Wars over $1,000 (or probably motivated for revenge).
- Jimmy Pegorino crosses it when he shoots Kate to death in Roman's wedding. During the ensuing chase, he even mocks Niko about Kate's death.
- Grand Theft Auto IV: The Lost and Damned:
- Billy using the death of a friend to steal some heroin, bragging about banging Ashley, or betraying his so-called brothers for a reduced prison sentence all qualify.
- Ray Boccino crosses it with Jim's brutal torture, and eventual murder.
- Grand Theft Auto IV: The Ballad of Gay Tony:
- Ray Bulgarin crosses this when he shoots his own sister out of anger and possibly killing her... and then he does it again almost immediately afterwards when he sends Luis to pick up a "gift", which turns out to be the severed head of the man Luis and Tony bought the diamonds from.
- Rocco sets up Luis to kill Tony Prince when an Ancelotti boss demands a body of either Luis, Tony or both of them in a shootout.
- Grand Theft Auto V:
- Franklin crosses this if Ending B is chosen, when he chooses to kill Michael. He chases him on the railings, ruthlessly beats him, and ultimately you have the option to make him fall from the tower, killing him. A lot of players were surprised at Franklin's ruthlessness in this mission. Not even Trevor was able to do that.
- Both Franklin and Michael cross it if Ending A is chosen, when the former chooses to kill Trevor. Trevor pleads with Franklin, telling him he has been nothing but straight and true with Franklin. When Michael stops Trevor at the oil field, a physically and emotionally broken Trevor lashes out at both of them, calling them Judases and fake motherfuckers before one or the other executes him. After Trevor dies, Michael tells Franklin to grow up and then rants about how Trevor was a psychopath.
- If Trevor didn't cross it by killing Johnny, and then wiping out ALL of the Lost's former Alderney chapter, he has several other good contenders, most notably his collusion with the Altruist Cult. However, he is betrayed by this cult.
- Incredibly avoided both in Ending A and B. In both endings, he's not willing to kill Franklin or Michael, even though in Ending A they're trying to kill him.
- Devin crosses it when he sends Merryweather after Michael's wife and daughter.
- Steve Haines crosses it with the infamous, long, drawn-out torture of Mr. K. There are a number of factors which contribute to make this scene a particularly brutal crossing. For one, it's obvious that Mr. K is innocent of completely any wrong-doing whatsoever, he just happened to briefly work for someone who the FIB was suspicious of. The other factor is that, even though Mr. K knows next to nothing useful, he's still one hundred percent willing to share everything he does know with Haines. It's just that Haines has Trevor torture Mr. K before interrogating him, avoids asking Mr. K direct questions, and when he does ask direct questions he rarely gives Mr. K enough time to respond before opting to have Trevor torture him more. Because of his sadism and impatience, Mr. K gets knee-capped, electrocuted, has a tooth ripped out with pliers, and is water boarded with gasoline. He then caps it all off by ordering Trevor to kill Mr. K before skipping off merrily to go play racquetball. Fortunately, Trevor goes behind his back by waiting for him to leave, releasing Mr. K, and driving him to the airport instead.
- The Minute Men cross this when they draw real guns on an innocent family of legal immigrants and get ready to execute them. Or at least, they would have if Trevor hadn't come along and killed the two of them.
- Peter Dreyfuss actually crossed it 38 years before the game's main plot via the brutal murder of Leonora Johnson. To be more specific, he cut off both her hands and feet and placed them in opposite areas, cut off some of her face, left multiple wounds on her breasts, drew a star on her back with a cigar, sliced off a portion of her thigh and then wrote "HAM" on it, and finally decapitated her. After Leonora died, he had sex with her corpse and tormented her family for several years by sending them letters and, on the anniversary of her murder, her severed lips.
- In Grand Theft Auto Online, Avon Hertz and his AI companion, Clifford, cross this during the second act of the Doomsday Heist when they betray the protagonists and take control of the government with Clifford wanting to commit genocide on the human race.
- Cliffford goes even further when he reveals that he wants to kill Avon when he will outlive his usefulness.
