The almost entirely true story of Abraham Lincoln and his self-appointed bodyguard, U.S. Marshal Ward Hill Lamon - a banjo-playing Southerner who foiled repeated attempts on the President's life, and kept him functioning during the darkest hours of the Civil War.

Mary Shannon is a U.S. Marshal in the witness protection program who spends her time relocating federal witnesses.. Based in Albuquerque, New Mexico, Mary works with her partner, Marshall Mann, to place criminals and innocent witnesses into new lives. When not putting her life on the line to protect federal witnesses, Mary attempts to manage her dysfunctional family, including overly dependent mother, Jinx, and younger sister, Brandi, both of whom live with her. Between work and family, Mary has little time for boyfriend Raphael Ramirez who plays minor league baseball.

U.S. Marshal Carrie Stetko is three days from the end of her tour at an international research station in Antarctica after which she'll resign. An incident from her past haunts her. The continent's first winter storm is coming when a body, wearing no gear, is discovered in the tundra. She investigates, soon finds more bodies, and must find a motive and a murderer before the storm and her departure. A U.N. agent, Robert Pryce, appears, seemingly out of nowhere, to help. An aging physician about to retire, a nervous mission chief, a downed Soviet plane, and the weather's deadly elements add to the story. Can Carrie trust Pryce and does she still have what it takes?