As Monica and Tess discuss the end of winter, Tess reminds Monica that in some places winter lasts all year round. One such place is the Kewanee Women’s Correctional Facility where Monica’s assignment, Carla Robinson, is doing 25 years to life for murder. Monica joins the prison staff as a social worker and begins to implement a prison theater program. With Tess’ help as a prison guard, Monica is able to get a small group of the prisoners to open up about themselves and their crimes. Carla though claims to be innocent and spends her time trying to get a pardon.

Meanwhile, Andrew is a hospice nurse to Santos Gonzales, the father of Orbie, the man Carla was convicted of murdering. Even after several years, Santos is still bitter about Orbie’s death. At the prison, Monica chooses the play “Agnes of God” for the women to perform for the rest of the inmates. “Agnes of God” tells the story of a young nun who becomes pregnant as a result of being raped. Agnes is accused of murdering the baby, though she has blocked out any memories of the incident. Monica casts Carla as Agnes. As rehearsals commence, Monica begins to believe that Carla may be innocent of her crime, but Andrew arrives to say that Carla is guilty — he was there. Tess tells Monica that Carla isn’t simply lying – she actually believes that she is innocent, and, like Agnes, has blocked her memory of the tragic event.

As Santos gets closer to death, Andrew pleads with him to pray for peace rather than for vengeance against Carla. Monica begins to make progress with Carla, learning of her suicide attempts and the daughter she hasn’t seen in years. When Monica asks Carla about Orbie, she gives her version of the events — that her boyfriend, conducting a drug deal, shot Orbie, an innocent bystander. Before Monica can challenge this version of events, Carla receives news that her conviction has been overturned. Despite her imminent release, Carla agrees to still participate in the first performance of “Agnes of God.” During the climax of the play when Agnes regains the memories of her own tragedy, Carla begins to have flashbacks about Orbie’s death — and about her involvement.

Though upset, Carla finishes the show and is soon released from prison. When Santos hears of Carla’s pardon, he insists on asking her forgiveness for all the years he’d cursed her. Carla meets her daughter Meredith for a tearful reunion at a local diner where Tess “moonlights” as the waitress. Andrew arrives with Santos but Carla is too overwhelmed to speak with him. In the storeroom, Monica reveals to Carla that she is an angel and helps Carla pray for the ability to remember the truth. Carla finally recalls that she accidentally pulled the trigger in a drug-induced haze. She begs for God’s, and then Santos’, forgiveness and then tells Meredith that their life together will be postponed — she must first go to the court and tell the truth.