Robin Williams will return to prime-time series TV for the first time in nearly a decade in a sweeps episode of "Law & Order: SVU" in late April.

Williams will play a man whose life is falling apart, and the actions he takes as a result bring the detectives of Special Victims Unit into the picture. The episode -- the show's 200th -- is scheduled to air Tuesday, April 29.

"We are thrilled that one of the most talented and versatile actors around will be starring in this powerful and complex special 200th episode," executive producer Neal Baer says. "We can't imagine anyone else doing this role."

The Oscar-winning actor ("Good Will Hunting") is, of course, no stranger to television, having broken out on "Mork & Mindy" in the late '70s. Since beginning his film career, though, his series appearances have been limited. His last guest-starring gig was on "L.A. Doctors" in 1999; he also earned an Emmy nomination for a guest role on "Homicide" in 1994.

Recent credits for Williams include "License to Wed," "August Rush," "One Hour Photo" and "Insomnia."

In the "SVU" episode, Williams will play an engineer whose life is hit by tragedy. In its wake, "he becomes an ardent believer in the necessity of challenging authority," NBC says. "His purpose in life turns to making people aware that there are risks posed by leading unquestioning lives."

"Law & Order: SVU" returns from its strike-induced hiatus on Tuesday, April 15.