Sarah Jones as Rebecca Madsen, a San Francisco homicide detective
Sam Neill as Emerson Hauser, an FBI agent and former police officer who arrived on the dock at Alcatraz to find the prisoners gone in 1963.
Jorge Garcia as Doctor Diego “Doc” Soto, a PhD in both Criminal Justice and Civil War History, author of books on Alcatraz and comic book store owner, writer, and artist.
Parminder Nagra as Dr. Lucille “Lucy” Banerjee, Agent Hauser’s technician/colleague.
Robert Forster as Ray Archer (previously Ray Madsen), Det. Madsen’s great-uncle and former Alcatraz prison guard.
Santiago Cabrera as Jimmy Dickens, a SFPD officer and Det. Madsen’s fiancé.
Jonny Coyne as Edwin James, the warden of Alcatraz.
Jason Butler Harner as Elijah Bailey “E.B.” Tiller, the merciless deputy warden.
