Starring in a TV show for 15 years can take a toll.

This week, Lynette Rice’s new book How to Save a Life: The Inside Story of Grey’s Anatomy is out, and in an excerpt obtained by HollywoodLife, actor Justin Chambers opens up about his exit from the show.

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Chambers, who played Dr. Alex Karev on “Grey’s Anatomy”, starred in the show from its very first episode in 2005, finally departing in early 2020 with a heartbreaking farewell.

But in the book, Chambers describes how working on the show for so many years began to feel routine.

You’re in a bubble [on the show],” he said. “You wear scrubs every day, you see pretty much the same people every day, in the same four walls, the same studios, you drive the same route to work. For me it [was] sort of a factory job for acting. You just clock in, clock out. Yeah, I guess it is sentimental, but it’s sort of like, ‘Wow, I just can’t believe how fast it’s gone.’”

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The actor’s comments are in line with his original statement announcing his departure in 2020.

“There’s no good time to say goodbye to a show and character that’s defined so much of my life for the past fifteen years,” he said at the time. “For some time now, however, I have hoped to diversify my acting roles and career choices. And, as I turn fifty and am blessed with my remarkable, supportive wife and five wonderful children, now is that time.”

Fans will get to see plenty of Chambers in the upcoming show “The Offer”, about the making of “The Godfather”, in which he will play iconic actor Marlon Brando.