Mary Shannon

Tough, sexy and smart Mary Shannon (Mary McCormack) is a U.S. Marshal attached to the highly secretive Federal Witness Protection Program known as WITSEC, assigned to Albuquerque, New Mexico.

Her job of protecting Federal Witnesses—from career criminals to innocent bystanders—is tricky enough, but it's even trickier when dangerous people want those witnesses dead. On top of the myriad responsibilities attached to her high-risk job, Mary must keep the true nature of her work secret from her family and friends in order not to endanger them, her witnesses or herself.

To help facilitate her witnesses' often rocky transition into their new lives, she has to wear many hats at any given time: mother, therapist, best friend, maid of honor, priest, rabbi, marriage counselor, employment agent, bodyguard, and occasionally, homicide detective.

As far as Mary's loopy mother, Jinx, and her younger sister, Brandi, are concerned, Mary's job as a Federal Marshal consists of lounging around the courthouse with her trivia-loving partner, Marshall, and serving the occasional warrant. It's hard not being able to tell the people she's closest to what she does, but truth be told, she prefers it that way. The last thing she wants is for anyone to have to worry—that's her job, both on duty and off.