The Terminator 2 actor joined the action thriller in February, signing up to play Master Chief Joseph Prosser.
Patrick has now been made a series regular after guest-starring in the pilot episode, TVLine reports.
The 53-year-old is known for his roles on The X-Files and The Sopranos. He also previously worked with Last Resort creator Shawn Ryan on The Unit, which ran on CBS between 2006 and 2009.
Last Resort follows a nuclear submarine crew who become fugitives after refusing to fire their missiles. Taking refuge on a small island, the crew establish themselves as the world's smallest nuclear nation.
Andre Braugher (Homicide: Life on the Street), Scott Speedman (Underworld), Autumn Reeser (The OC) and Dichen Lachman (Dollhouse) also star in the series, which will air on Thursdays at 8/7c this fall.
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Watch a trailer for Last Resort below: