'SNL's' Jason Sudeikis Digs Up Family Secrets on 'Who Do You Think You Are?' (Exclusive Video)

Jason Sudeikis Who Do You Think You Are? Screengrab 2012

Saturday Night Live star Jason Sudeikis discovers some startling family secrets that may have been swept under the rug on Friday’s episode of NBC’s Who Do You Think You Are?.

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The 36-year-old actor takes the plunge into his family’s history on the documentary series and he’ll be shocked by what he finds. One of the first familial trails he’ll follow is that of his paternal grandfather. He died when Sudeikis’ father was still a child, leaving his grandmother with their two children. But upon some digging, the actor finds out that he was absent from their lives way before his passing.

In The Hollywood Reporter’s first look at the episode, it seems as if Sudeikis’ grandmother chose to keep several details of her marriage a secret. But, court documents will reveal a startlingly different image of the actor's grandfather than the one he had grown up with.

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That’s really only the beginning of his journey as the star continues looking into his family’s history, which includes roots in America’s coal mines and a connection to Lithuania.

Watch the preview below.

Who Do You Think You Are? airs Fridays at 8 p.m. on NBC.

Email: Jethro.Nededog@thr.com; Twitter: @TheRealJethro

look through phone directories for forty minutes, if that's all [they] did," the producer and actress jokes with THR."]