LOS ANGELES, California (Hollywood Reporter) -- NBC's casino drama "Las Vegas" is set to return for a fifth season in the fall without two of its stars, James Caan and Nikki Cox.

Caan wants to return to movies, while Cox's departure is said to stem from budget cuts. The show boasts a large ensemble cast and has moved from Mondays to Fridays, where viewership levels are lower.

Caan, Oscar-nominated for his turn as Sonny Corleone in "The Godfather," made his first foray into TV series with "Las Vegas," in which he plays the surveillance boss at a casino.

"I've had a wonderful four years, worked with great people and made friends for life working on 'Las Vegas,' but I'm eager to return to where my heart is, which is film, and due to the show's schedule, I missed some great opportunities to do that," Caan said. "I wish the show and everyone involved with it continued success."

In a 2005 Playboy interview with Playboy, Caan was less than enthusiastic about the show, saying that he never watched it, and that it sometimes strained credibility.

As for Cox, who plays a comely casino hostess, she said she was "very sad and shocked ... I wish them all the best of luck and had a great time working on the shows." Cox recently married comedian Jay Mohr.

"Las Vegas" ranks as the top program in the 9 p.m. Friday slot among adults 18-49, averaging a 2.8 rating/8 share in the demo and 9 million viewers.