LAPD detective Erin Bell arrives on the scene of a
John Doe murder and informs the responding officers that she knows the identity of the murderer. At the police station, Erin receives an unmarked envelope with a $100 bill stained from a
dye pack. Using a contact at the
FBI, she confirms that the bill is from a bank robbery committed by a California gang 16 years prior that her former partner, FBI agent Chris, and she were embedded in as undercover officers. She tells her superiors that she believes the bill to be proof that the gang's leader, Silas, is once again active. Erin works her way through the remaining members of the gang to find Silas. She begins with Toby, who was in prison, but is now gravely ill and living with his mother on
compassionate release. She gives him a
handjob in exchange for the location of Arturo, a member of the gang atoning for his past crimes by offering
pro bono legal services to immigrants. Arturo provides Erin with the location of Dennis DiFranco, a lawyer who launders the multimillion-dollar haul from the original robbery and from whom Erin deduces that Silas is active again because the money from that heist is almost gone. After Erin thrashes him, DiFranco gives her the location of the next money drop, which is performed by Silas' girlfriend Petra, who has developed a severe drug addiction. Erin tracks Petra, eventually intervening in a bank robbery committed by Silas' new gang. Petra and she brutally injure each other in a fight, ending with Erin abducting Petra.
Flashbacks reveal that Erin and Chris developed a romantic relationship while undercover, with Erin eventually becoming pregnant, later having their daughter, Shelby. At Erin's behest, they decided to become legitimate participants in a bank robbery and planned to take their shares of the heist, report to their superiors that they lost contact with the gang, then eventually quit the force. The robbery was botched when a dye pack exploded in one of the bags, and Silas killed the bank teller who accidentally placed it. When Chris attempted to intervene, he was shot and killed by Silas. Erin, in favor of her unborn daughter, did not interfere in Chris' fatal shooting, instead fleeing the scene with the other robbers. After crashing the van against a dumpster and seriously injuring Toby, Erin hid her share of the heist and returned to policing, disclosing neither her original plan nor her share of the heist. Erin turns to drinking and medication due to the guilt of this deception and her anger over choosing her daughter's life over Chris's. In the present, Erin visits Ethan, Shelby's adoptive father, and later talks with Shelby. Erin visits a
self storage unit to retrieve her $300,000+ share of the stolen money, but finds that all but $11,000 is stained with dye. Silas sends a text message to Petra's phone, instructing her to meet him at the Bowtie Park, where Erin confronts and shoots him, avenging Chris. She returns the next morning to find the police investigating the crime scene, the John Doe murder investigation depicted in the first scene of the film. With Silas dead, Erin gives evidence of her guiltwhere he can find Petra, a stained bill, and the key to her storage unitto her partner, Antonio. Erin has been bleeding internally for hours, from injuries she sustained during a beating by DiFranco's bodyguard and in her fight with Petra, and she dies while sitting in her car. In a flashback scene we see Erin make peace with her daughter. ==Cast==