Carter meets a new pedes intern, Rena Trujillo. He and Luka are then dispatched to the site of a major train wreck. Carter must perform a tricky double amputation on an injured firefighter after Corday goes into early contractions at the scene. After Elizabeth returns to the hospital, Abby and Chen treat Corday, who is told to stay on bed rest. Benton lets prospective med student William White follow him around the ER. Weaver calls Legaspi for a psych consult on a suicidal girl who caused the train crash by driving her car onto the tracks. Luka wrestles with his faith, revealing that he could have saved his wife by sacrificing his daughter. Bishop Stewart grants him absolution before his death.