Johnny has an obsession with guns, and prefers to blow everything up rather than being stealthy. Johnny is constantly referred to in Saints Row when the topics of violence or weapons come up. When Dex is giving the rundown on Los Carnales, he advises the player to take it safe and "not pull a Johnny." He is referred to several times when the player goes to gun shops, with the shop keeper making comments when the player buys some of the bigger weapons in the game (such as a rocket launcher.)
Johnny Gat is voiced by Daniel Dae Kim, best known for his role as Jin Kwon on the T.V. series Lost.
Role in Saints Row
Troy was original assigned to take care of the Vice Kings in the first game, but he turned the "offer" down (because of their ties to the Stilwater Police and him being a undercover cop) so Johnny gladly stepped in. Julius didn't think that he was ready, so he assigned Dex to look after him.
Johnny's first day on the job starts with his girlfriend Aisha's sister being captured. It turns out that the Vice Kings have been picking up girls of the row and forcing them in to brothels. Johnny sends the main protagonist to retrieve her. After she is brought back, Johnny and Aisha decide to break Aisha's contract with Kingdom Come Records, the company run by Benjamin King. Johnny sends Aisha to a recording session in a car rigged with explosives. When she arrives, she sneaks off through the back and the bomb goes off outside, destroying the building and framing Aisha's death.
After causing plenty of damage to the Vice King rep by taking out a few brothels, Johnny decides to raid Vice King hideout in a abandoned police station were Tanya is staying. After cornering her on the top level, Johnny and the protagonist are ambushed from behind by Big Tony. After Johnny runs his mouth one too many times Tony shoots him in the leg. Johnny then stabs him in the foot and knocks him down long enough to allow the main character to get away. Johnny is eventually rescued by the main character. After being untied, Johnny vents by emptying his clip into Tony and throwing his gun at him. It is very apparent that his leg is seriously wounded. While Johnny was tied up, he heard Big Tony talking about some heavy artillery in the back. He has it brought back to the church for later use.
After Johnny's return to the row, Dex begins to work with him since his "shoot everything" approach is not working. After they join forces, a combination of strategy from Dex's part and rockets from Johnny, the Vice Kings are forced to sever their ties to the police. To celebrate, Johnny takes Aisha out on a date, only to come back to find Warren dead, King severed from the VKs, and Tanya in charge of the gang. After King agrees to help the Saints take out his own gang, Johnny Gat, Benjamin King, and the "Player" go to take the Vice Kings out permanently. However, to reach Tanya, they need the code to the elevator. Tanya has had the common sense to change it from Ben's code. In an attempt to find out the code, the trio abduct her hairdresser and interrogate him. The interrogation involves Benjamin swinging the guy out of the car window. The main character then simply drives like a maniac until the hairdresser reveals the code, upon which Benjamin lets go of his leg. The three then fight their way through King's penthouse and shoot Tanya out of the window before King knocks her off, killing her.
Johnny and Lin seemed to get along like brother and sister. When Lin was killed in the Westside Rollerz storyline Julius says that Johnny should take it pretty hard and he'll be out for blood. The main character never actually sees a reaction from him though.
After Julius' arrest and the murder of mayoral candidate Marshal Winslow, Police Chief Monroe still refuses to release Julius. Dex, Johnny and the protagonist are left to decide what to do. Johnny would like to blow up city hall, but instead the remaining Saints decide to kill the Police Chief at Winslow's funeral.
Role in Saints Row 2
A year before the start of Saints Row 2, Johnny Gat attempts to murder Troy (now police chief). Gat is arrested and sent to death row charged with one count of attempted murder and 387 counts of murder. During his appeal at the beginning of the game, the Player breaks into the courthouse and rescues Johnny.
Back on the streets, Johnny and the Player (now the Boss) need new headquarters since the old church is now a tourist attraction. They take over a new hideout under the Red Light District where an earthquake buried it underground. They clear out the spot of homeless and gang members and make themselves comfortable. To help rebuild, Johnny gives the Boss the locations of a couple of possible lieutenants, Shaundi and Pierce, who eventually become just that. He also gets together a bunch of other lackeys and initiates them them like the Player in the first game.
In Saints Row 2, Johnny is no longer a lieutenant and more of a co-leader of the new 3rd Street Saints, thus he has more of a executive role. Although he still portrays the psychopathic gangster who is always looking to kill a few punks.
Johnny is seen frequently in the prologue and final missions, and he plays a large role in the Ronin storyline. Johnny kills a member of the Ronin he caught sneaking around his house, blowing his brains all over Aisha's carpet. The next time Johnny Gat and the Boss return to Aisha's house, Jyunichi and some Ronin have taken Aisha hostage and are preparing an ambush for them. Aisha tries to yell to Johnny and the Boss to warn them before they enter the house, but Jyunichi cuts her off by cutting off her head. The two of them manage to fend off the Ronin, but Johnny ends up getting stabbed by a katana and Jyunichi escapes for the time being.
Johnny continues to have a role throughout the Ronin storyline, culminating in Johnny and the Boss being attacked at Aisha's funeral, and afterwards burying their leader Shogo alive. Johnny is never seen in the Brotherhood or Sons of Samedi missions, probably because the three story arcs can be completed in any order and it wouldn't make sense for him to participate in any of those missions while he's supposed to be in the hospital during the middle of the Ronin story arc.
Role in Saints Row: The Third
As Saints Row: The Third opens, Gat and the rest of the Saints have become international celebrities and media superstars. At the start of the game, he, the Boss and Shaundi plan a bank heist with actor Josh Birk tagging along, and all of them disguise themselves as Johnny Gat (including Gat himself). However, when the heist goes wrong, the Saints find themselves abducted and imprisoned on a plane owned by Phillipe Loren, leader of Morningstar, a gang in Steelport, as well as head of the Syndicate, comprised of Morningstar, the Deckers, and the Luchadores. As the Saints fight for their escape, Gat is injured, but makes his way to the cockpit to fly the plane back to Stilwater. However, Loren and his men corner Johnny and kill him. Gat's death leaves a profound impact on the Saints, particularly Shaundi, and it is in part because of his death that they fight to take control of Steelport.
Although Gat dies within the opening minutes of the game, his presence is still felt in Steelport. Players will encounter NPC mascot characters wearing Johnny Gat costumes, and there is even a unique vehicle called the Gat Mobile; a purple van with the front designed to look like Gat. Appropriate to his love of causing havoc, the Gat Mobile is equipped with a flame-thrower.
Upon completion of the game, the player will unlock Zombie Gat as a homie, continuing the tradition where killed Saints characters are brought back as zombies ( Lin in Saints Row and Carlos in Saints Row 2).
The DLC chapter The Trouble With Clones revolves around a fanboy who attempts to clone Johnny, only for the result to be a brutish creature the size of Oleg who seems frightened and confused by Steelport. The clone survives the DLC, and "Clone Johnny" is unlocked at the end of the chapter, so it is unknown whether this Johnny, or any Johnny, will make an appearance in The Next Great Sequel in the Saints Row Franchise.