Michael Douglas and Scarlett Johansson not only share successful acting careers but are also linked by blood, as revealed on the April 2 episode of PBS's "Finding Your Roots." During the show, host Henry Louis Gates informed Douglas that the Marvel star, and his co-star in "Avengers: Endgame," is his DNA cousin.

"Are you kidding?" Douglas exclaimed upon hearing the news. "Oh, that’s amazing. All right. This is cool. This is so cool."

Gates further explained that research conducted by professional genealogists revealed that the 79-year-old Douglas and the 39-year-old Johansson "share identical branches of DNA on four different chromosomes." Notably, all of these shared branches trace back to Johansson's maternal line and extend to Eastern European Jewish communities.

Douglas, renowned for his role in the film "Wall Street," is the son of the late actor Kirk Douglas, who was born to Russian Jewish immigrants.

"That's incredible," Douglas remarked upon learning the new information.

Interestingly, Douglas wasn't the only celebrity to discover a familial connection with Johansson on "Finding Your Roots." Andy Cohen also learned of his relation to the Marvel actor during his appearance on the show.

In the same episode, Douglas stumbled upon his link to a significant figure in American military history: John Neilson.

As per the episode's account, Neilson furnished military intelligence to George Washington during the Revolutionary War. When the Revolutionary War erupted, Neilson, initially a merchant, opted to back the Continental Army rather than remaining loyal to England. Presently, a statue in New Brunswick, New Jersey, commemorates his contributions.

Gates proceeded to elaborate on how, on July 9, 1776, John stood at a table in front of a tavern in New Brunswick and recited the Declaration of Independence aloud. His was the third official public reading of the document.

Neilson would swiftly ascend to the rank of colonel in a New Jersey militia. In February 1777, he would participate as the militia assisted in attacking a British stronghold in the Battle of Bennett’s Island. According to Gates, Neilson would later become a slave owner.

"I mean, he’s inspirational other than the fact that he was still a slave owner," remarked Douglas.

“I think the overwhelming feeling for me is for him to risk as early as he did reading that Declaration of Independence is a very courageous act. And his war record is amazing,” he continues. “And you just try to equalize that with having slaves 40 years later.”