It's rare for a British period soap opera to become a cultural phenomenon, and it's even rarer for it to net an A-list movie star.  Downton Abbey, arguably the silliest drama on television, is set to premiere a short film on their British network ITV over the holiday season to promote the network's "Text Santa" charity initiative.  George Clooney will pitch in by making a guest appearance, although there are currently no details about his character or the size of his role.

A brief clip from the special has been released online, and it provides no further information other than Cora looking like she's mistaken his character for Lord Gratham.  Or perhaps she's just calling him "Dearest" because, let's face it, George Clooney is everyone's dearest.  Hit the jump to check out the Downton Abbey short film clip.  The movie will premiere on ITV on December 18th.  The show's fifth season has already aired in the U.K., and will premiere in the U.S. on January 5th on PBS.

Via EW.

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