George Clooney plans to return back to the medical drama that launched his career NBC's ER.

Sources confirm to Entertainment Tonight that Clooney will be scrubbing in once again as Dr. Ross.

Clooney was last seen in a cameo role on the show in May 2000, but left in February 1999.

It's not clear how many episodes will feature Clooney and NBC spokesman said Wednesday the network was not confirming the Clooney reports. Clooney's publicist was also not able for a comment.

The show that is in its final season, has been featuring appearances from its early cast members including Anthony Edwards, Noah Wyle, Abraham Benrubi, Eriq LaSalle and Alex Kingston.