George Clooney is rumoured to be starring in the last ever episode of ER.
US reports claim the actor, 47, began filming scenes this week.
'We're going to have a lot of people coming back to ER at the conclusion of the series,' producer John Wells tells Us Weekly.
'George is very busy. He's very handsome. We've talked about it a couple of times. You know, it's George'
In September, the star denied reports he was returning to the show.
The finale of the NBC series will be screened in April.