"ER" alum George Clooney will be returning to the Warner Brothers lot for one last episode, sources told RadarOnline.com.

Clooney reportedly will take over his role as Dr. Doug Ross, in a secretive shoot that only a few cast and crew members will be allowed to see.

The show is entering its final season, after 14 years on the air.

Clooney also joins other ER alums Noah Wiley, Anthony Edwards and Alex Kingston who have returned to reprise their roles.

Click here for more on this report from radaronline.com.