Chris O'Dowd and Nigel Tufnel working together on a mockumentary for HBO?!? *fans self*

Digital Spy reports: "Family Tree - a mockumentary like much of Christopher Guest's past work - will focus on a man (O'Dowd) who is searching for his long-lost relatives and stumbles across a string of unusual characters and stories. Guest will executive produce the series with Jim Piddock (The Five-Year Engagement), with both men also expected to appear in the show."

The BBC’s executive editor for comedy, Chris Sussman, said: "We are all ludicrously excited about the opportunity to work with Christopher Guest. He has British roots but this is his first ever project over here, and we are very pleased to have it on the BBC."

Mario Stylianides, head of comedy at producers Lucky Giant said: "Family Tree will feature Christopher's signature style in a humorous look at the ties that bind our families."

So, essentially they'll be taking the piss out of Who Do You Think You Are?

The show will air on BBC2 on this side of the Atlantic, and HBO stateside.

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