|“||You gotta keep my daughter safe. Please.||”|
Polinsky got a job as a prison guard at the Reagan Federal Penitentiary, and he took his job seriously and ethically. In his personal life, he had a daughter, who he cared a lot about. One night, while looking for another guard, Keith Rivers, Polinsky accidentally stumbled upon him, his boss Dale Shavers, and several other guards standing upon the body of Devon White, a new inmate. Nearby was another inmate, bank robber Patrick Butler, who had been forced to beat Devon by Shavers, although the death was an accident. Polinsky was forced to help dispose of Devon's body, then was confronted by Shavers, who threatened to kill his daughter if he talked. As a result, he stayed silent about the whole ordeal. However, he became ambivalent and began assisting Butler and several other inmates in killing people connected to Shavers and his gang, including Rivers. Because he wasn't a killer, Polinsky only provided the inmates with keys to rooms most inmates weren't allowed access to.
Polinsky is first seen letting the BAU inside the prison building. Later on, he goes into the locker room, opens his locker, and finds, to his horror, a photo of his daughter marked with a red X. The next day, he is confronted by Shavers in the locker room; he tells him that he remembers not to tell anyone about what he saw. While he does, Shavers begins to taunt Polinsky's daughter. Later on, Polinsky is among those being interviewed by Morgan and Kate. He finally caves in and, realizing that Shavers is likely watching, whispers to the agents, begging them to keep his daughter safe. However, before he can give Morgan and Kate anything, inmates suddenly appear and take over the interrogation room. Polinsky, Morgan, and Kate fight back, but the inmates overpower them and take them hostage. During the fight, Polinsky gets stabbed twice with a shiv by Don Black. Later on, the inmates take the three of them to the prison cafeteria, where Polinsky begins to bleed out from his injuries. Agitated, Black keeps kicking Polinsky until he gets shot by a sniper, while a SWAT team breaches the cafeteria and arrests the other inmates. Polinsky is last seen being taken out on a medical stretcher, but it is unknown if he survived, given the severity of his injuries.
- Polinsky is last seen being taken away on a hospital stretcher, but there is no confirmation if he survived the critical stab wounds inflicted on him