Rob Lowe is joining the second season of Code Black.

Lowe previously appeared on the Fox comedy The Grinder last year, but is making the switch to drama. CBS announced on Tuesday that Lowe will play Col. Ethan Willis on the CBS hospital drama this fall as a series regular.

Willis is a doctor in the U.S. military's prestigious combat casualty care research program. He was pulled out of a combat hospital in Afghanistan and placed at Angels Memorial to teach what the military has learned about combat medicine. His "aggressive, rule-breaking style is greeted enthusiastically by Dr. Leanne Rorish (Marcia Gay Harden)."

The news comes after Lowe said that he'd be hesitant to return to a broadcast show if The Grinder was canceled.

Here are CBS' fall premiere dates

"If the show doesn't get picked up though, I really need to examine what I have to offer on network television in this climate because I do a certain type of show — West Wing, Parks and Recreation, The Grinder — and my sense is that is really no longer where network television lives," he told The Hollywood Reporter earlier this year.

Code Black has gone through a few casting changes already as it heads into the sophomore season. Series regulars Bonnie Somerville and Raza Jaffrey left after the first season. The show has also added Noah Gray-Cabey, Emily Tyra and Nafessa Williams to their second season.

Code Black Season 2 premieres Sept. 28 at 10/9c.

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