Susan Sarandon, George Clooney

There have been lots of rumors about George Clooney's return to ER. Here's the latest news: Oscar winner Susan Sarandon will share some scenes with Clooney, according to E! Online.

NBC wouldn't confirm or deny either Clooney or Sarandon's guest-starring gigs on the medical drama, and calls to the actors' reps were not returned. As a result, plot details are being kept under wraps (literally — the set is closed this week). But why should that stop us from speculating wildly about what might bring grumpy kid-doc Doug Ross back to the County General fold, with Sarandon in tow?

Here are our three "best" guesses:

1. Doug and his wife, Nurse Carol Hathaway, are in Chicago for a big fat Greek wedding when one of their 9-year-old twin daughters (let's say Tess) fractures her ankle ice-skating on Lake Michigan. When they bring her into County General for treatment, they meet Sandee (Sarandon), a slutty new desk clerk who snaps her gum and makes sexually suggestive comments to Frank.

2. Sarandon plays grieving mother Emily Atwell, whose daughter, Kim, recently died under suspicious circumstances at County General. Doug was listed as Kim's emergency contact. When Carol learns of their emotional affair (they met in a chatroom called "Married But Not Dead"), she leaves Doug and returns to County to try to get her old job back. Rick Rossovich cameos as Carol's ex-fiancé, John "Tag" Taglieri, who appears to have changed his mind about taking the plunge.

3. Sister Louise (Sarandon), a kindly nun who runs a local orphanage, recounts, via flashback, the story of a former volunteer named Doug Ross, who recently died in a freak hang-gliding accident in Maui. As Ross' history with the orphanage unfolds, it's revealed that Ross himself fathered all the children who lived there, and that his generosity was, in fact, court-ordered.

Now you try. What do you think brings Clooney back to County? And how does Sarandon figure into the story?

Watch full episodes of ER in our Online Video Guide