Joe Manganiello finds out he's descended from slaves and uncovers a mystery on Finding Your Roots

For anyone, taking a deep dive into your family roots can turn up a lot of surprises, not all of them welcome. Finding Your Roots on PBS had that in mind when they contacted Joe Manganiello to see if he wanted to opt out of his episode—something it rarely does.

Manganiello's lineage is full of more dramatic twists and turns than the final season of True Blood, but he went through with his episode and he and host Henry Louis Gates even presented a special screening of it in Los Angeles, a first for the series. Watch his reaction to "meeting" one of his unknown ancestors in the exclusive clip above.

"If I have a short list of all-time greatest hits, Joe Manganiello's paternal ancestry is on that list," Gates told Rolling Stone.

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Well, let's start with the maternal side. Manganiello's great-grandmother Terviz "Rose" Darakjian was basically a superhero, surviving the Armenian genocide after her husband and seven of her eight children were murdered in front of her in 1915.

"It's virtually impossible that I exist," Manganiello told Rolling Stone.

Rose escaped with the eighth child, an infant, strapped to her back, swam across a river to escape death marches, only for her baby to drown by the time she got to the other side. She lived in a cave before she was picked up by German officers and taken to a camp, where she was impregnated by one of the officers.

Manganiello had known that his great-grandmother was a survivor of the Armenian genocide and his great-grandfather was a German officer, but he had never been able to find out his identity. Until Finding Your Roots. That officer's name was Karl Wilhelm Beutinger, and he already had a wife and three kids back in Germany, one of whom—his eldest son, Manganiello's great uncle—grew up to be a Nazi SS officer during World War II.

"You have to take the good with the bad," Manganiello said. "And there's some of that with history. I think there's a tendency to say, 'I'm so proud that my ancestors were on the right side of history,' but that's not you — that's somebody else."

And now the paternal side. After Manganiello took a DNA test, he found out that he's both 100 percent that bitch and 7 percent Sub-Saharan African.

"Sub-Saharan African means that basically you're descended from slavery, as it pertains to the United States, and I didn't know that's what it meant until I was on the show," Manganiello said.

The actor's fifth great-grandfather was Plato Turner, a man born in Africa and brought to the United States and enslaved as a child. He later became a free man and joined the Continental Army during the Revolutionary War, fighting against the British. There's a monument dedicated to him in Plymouth, Mass.

"It's so rare to think that you'd have freed slaves fighting for the Colonies," Manganiello said. "You fight for the freedom and the promise that all men are created equal, and then a hundred years later there's the Civil War? To think of how backwards this whole thing went…."

Manganiello's great-grandparents were an interracial couple, William Henry Cuter, a Black man, and Nellie Alton, a white woman, who wed in 1887 in Rhode Island — interracial marriage wouldn't be legal across the country for another 80 years. As a result of this union, Nellie's parents, Manganiello's great-great grandparents, disowned her.

"I'm descended from survivors," Manganiello said, noting that though the revelations of his family history are shocking, he feels like Finding Your Roots handed him a pair of glasses after all these years. "All of a sudden I can see myself clearly for the first time."

Joe Manganiello's episode of Finding Your Roots airs Feb. 9 on PBS.

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