After a presentation in Los Angeles, Lewis is approached by her ex-husband, Dr. Daryl Wright, who tells her somebody is killing recovering addicts. Bonnie Sullivan, a recovering addict, becomes the latest victim. Lewis tells the BAU about an unusual number of heroin overdoses among recovering addicts, eight so far. A wing tattoo is found on Bonnie's shoulder. Alvez and Simmons find no sign of Bonnie relapsing at her apartment. The unsub is using research chemicals on the victims, so the drugs can't be identified. Prentiss proposes that the unsub may be a recovering addict, and killing is his new addiction. The unsub kills another addict, Clay Miller, this time by smothering him. He had just been kicked out of his treatment program, for not doing the work. Dr. Robert Smith, the owner of Clay's treatment center, refuses to cooperate with the BAU. Another resident, Molly, passes Clay's journal to JJ. Lewis is remembering the good and bad times with Daryl. Smith isn't a real doctor. He's an ex-con and former drug addict who hates recovering addicts who don't work hard. Smith is threatening Molly when Alvez and Simmons come for him. He tries to run, but Simmons lays him out. Smith is a conman but no longer a suspect. Daryl's wife Mary comes to talk with Lewis. Mary says she's afraid Daryl will leave her for Tara. Tara thinks the unsub has a tattoo of the other half of the broken wing. Smith kicks out Molly as punishment. The unsub, Douglas Knight, offers her a ride. He had lost his wife to a drug overdose. He thinks he's putting addicts out of their misery. He's about to kill Molly when Prentiss and Simmons crash in. Lewis feeds words to Prentiss to convince Douglas to surrender. Prentiss saves Molly with Narcan.