James Spader is leaving the US version of comedy The Office.

The Crash star made his debut as oddball boss Robert California in the final episode of the last series and returned this year for the eighth season.

But NBC has announced James won't be back next year.

The Secretary actor was brought in to add star power to the cast after Steve Carell left the comedy last spring.

Paul Lieberstein, the show's executive producer, said NBC's initial commitment to James was only for last year's finale. But he said James' scenes proved so compelling "that those two scenes became a season."

He added that James had never wanted to stay beyond this year.