Jonny Frost, a low-level thug, is sent to
Arkham Asylum to pick up the newly released
Joker, who immediately takes a liking to Frost, using him as a chauffeur. Frost drives Joker to the lair of
Killer Croc. The three go to a strip bar called the Grin and Bare It. With the help of
Harley Quinn, Joker kills one of his former henchmen and claims his intention to make
Gotham City his again. Joker robs a bank and coaxes the
Penguin to invest the stolen money. Joker embarks on a killing spree, murdering many thugs who stole his money, turf, and bizarre sense of reputation. He is then informed by Penguin that
Harvey Dent, his chief rival for control of Gotham, is avoiding him, enraging Joker. Frost is detained by Dent, who warns him that Joker will kill him, but Frost delusionally believes he is an equal partner to Joker. Subsequently, Frost is late to Joker's meeting with the
Riddler, a disabled weapons dealer. They exchange a briefcase, and Joker and his crew leave. Once on the road, they are attacked by crooked off-duty cops hired by Dent, and Frost saves Joker's life in the scuffle. Joker embarks on a turf war against Dent, prompting him to meet with Joker at the city zoo. Bringing the briefcase he received from Riddler, Joker says he has learned Dent has two wives, and threatens to use the contents of the briefcase as leverage against him. Joker slashes Dent's wrist and Harley ambushes and executes his men. After helping Frost get his ex-wife Shelly back from Dent, Joker rapes her in front of Frost, saying this makes them "even", since Frost "cheated" on Joker by not revealing his own meeting with Dent. Later, Harvey paints
a bat on a spotlight to get
Batman's attention, and pleads with him to stop Joker. Joker and Frost flee from Batman, who subdues Harley and Croc in the process, and pursues them to a nearby bridge. While Joker is "screaming through tears", Frost inexplicably finds himself laughing, unable to stop. They find Batman in wait, and Joker demands to know why Batman disguises himself as a monster but spoils the illusion by leaving his mouth exposed. Batman replies, "To
mock you". Joker goes berserk and shoots Frost in the chin, leaving him with a
Glasgow smile. Joker and Batman fight as Frost climbs over the edge of the bridge and falls into the river, narrating that he has finally realized how ruinous his relationship with Joker was. ==Reception==