Former House M.D. star Jesse Spencer is still saving lives on the upcoming NBC drama Chicago Fire, only now he's putting his own at risk. ET Canada's Cheryl Hickey was on the set, getting the stars to dish on their intense training for the show. VIDEO: What Makes Chicago Fire Must-See TV? "They put us through simulation fires and things like that," said Jesse. While in these simulations, some of the actors had hair singed off and others almost vomited.