Paige Cooper

Under a powerful Mayan curse, snakes are hatched inside a young woman, slowly devouring her from within. Her only chance for survival is a powerful shaman who lives across the border. With only hours to live, she jumps on a train headed for Los Angeles. Unfortunately for the passengers aboard, they are now trapped, soon to be victims of these flesh-eating vipers.

Dr. Nathaniel Grant is a pioneering organ-transplant surgeon who takes risks that other doctors would not in order to save the lives of his patients. He works closely with his ex-wife, Kate Armstrong, an organ-donor coordinator with whom he has a volatile relationship. Grant's arrogance and willingness to perform risky procedures causes him to butt heads with the hospital administration. But his main focus is on his intense relationship with his job and his patients, often at the expense of his family.