Based partially on the infamous 1980 New Mexico Penitentiary Riot.
When entering the prison the guard tells Remmy and Kristen not to make eye contact with any of the inmates. Remmy tells Kristen "that goes double for you Greta Garbo". Greta Garbo was an actress, one of biggest stars of the silent and golden eras of Hollywood. She was known for her piercing gaze and eyes, plus she had a very melancholic and somber acting style, similar to Alexa Davalos, the actress that plays Kristen.
SORT stands for Special Operations Response Team, which is a unit of the Federal Bureau of Prisons. SORT units are designed and trained to be rapidly deployed in response to prison riots, escapes, hostage situations and attacks on prison staff and inmates.