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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.

"And that was just a simulation fire, so hats off to [professional firefighters]," Jesse continued.

The show, also starring Taylor Kinney (The Vampire Diaries) and Eamonn Walker (Oz), chronicles the lives of the firefighters, Rescue Squad and Paramedics of Chicago Firehouse 51. The series is said to find a happy medium between the action of the job and the drama of the characters' personal lives, which in turn affects their work relationships.

Watch the video for more. Chicago Fire premieres on NBC Wednesday, October 10 at 10/9c.