'Chicago P.D.': Who Killed Alvin Olinsky

Alvin Olinsky (Elias Koteas) was killed on Chicago PD in a tragic stabbing, but the team wasted no [...]

Alvin Olinsky (Elias Koteas) was killed on Chicago PD in a tragic stabbing, but the team wasted no time finding the person responsible.

After Alvin Olinsky (Elias Koteas) was stabbed multiple times outside of his jail cell, doctors rushed him to the medical wing of the prison and attempted to save his life, but not before one last heart-to-heart with best friend Hank Voight (Jason Beghe).

"Al, it's me," Voight says. "Be strong... hang in there."

"I got this man," Olinsky says to his friend.

After a long sequence of Voight waiting outside the operating room, a doctor comes out and breaks the news that Olisnky has died as a result of his injuries.

Voight then notifies the rest of the team, who are sitting in the waiting room. As the team grieves the loss of their friend, Voight enlists them to pick themselves sup and help find Al's killer.

"Let's put all our energy, our passion, our love for Al, and find the person who did this," Voight tells the members of the Intelligence Unit. "I know that's what Al would want... then when this is over, when we got this prick, then we'll mourn him."

Voight and the team inspect security footage and discover that the friendly corrections officer who advised Olinsky before deliberately left him alone to be attacked.

Voight and Antonio question the officer, he was paid an hour before the attack happened. Voight then questions the inmate who killed Olinsky and beats him up in a storage room to get information, despite the brutal beatdown the inmate says nothing.

Back at the police station, the team tries to figure out who would want Olinsky dead. The team finds out the inmate got a visit from a bogus attorney going by the name "Fidel Castro." They interrogate the man, who says he was hired by a man named Carlos De Leon.

The team uncovers that Olinsky worked in a federal taskforce trying to catch De Leon for laundering cartel money by arresting and trying to turn his little brother, but before they were successful De Leon's brother was killed in jail. Voight suspects the man could have targeted Olinsky in prison for revenge.

The officers follow the clues to De Leon's house, then to a warehouse where De Leon is hiding. Voight goes to the roof alone and confronts De Leo, who offers him money in exchange for his freedom. Voight then confronts him about Olinsky but shoots and kills him before he says anything else.

Antonio (Jon Seda) catches up and finds a gun in De Leon's waistband, but a community service worker yells at the officers from across the street saying that he saw Voight kill the man for no reason.

"You shot him in cold blood," he says. "You got no right to do that. No right at all."

The shooting leads to an internal investigation, with Antonio saying he didn't know what happened since he wasn't there, while Voight claimed he "feared for his life" and the matter is left at that.

After Voight settles his feud with Woods (Mykelti Williamson) once and for all, he binge drinks on a roof and mourns the death of his friend as the season comes to an end.

Chicago P.D. was officially renewed for a sixth season Wednesday night by NBC. When the series returns this fall, Voight will most likely continue to deal with the aftermath of the shooting, as the team reels from the loss of Olinsky.