The most unlikely kiss to ever happen on Downton Abbey.

Hollywood’s silver fox has an unusual cameo in an upcoming episode of Downton Abbey.

Downton Abbey is getting a visit from Hollywood royalty soon, with George Clooney set to star in the show’s annual Christmas episode.

Maggie Smith on Downton Abbey.

The highly anticipated cameo sees the silver fox attempt a kiss with the Dowager Countess, played by the incredible Dame Maggie Smith.

One of the show's stars, Laura Carmichael, who plays Lady Edith, told a British talk show that the Dowager Countess faints and falls off her chair after Clooney's character goes in for a peck.

The 53-year-old actor's cameo was a surprise to the whole cast, according to Carmichael.

“We were filming and then heard, ‘He’s here! He’s here! He’s arrived!’” Carmichael told The Mirror.

The Downton Abbey Christmas special will air on Christmas Day in the U.K, with an Australian air date to follow.

For now, CLICK THROUGH our gallery of George Clooney looking fantastic...

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