If you think you’re obsessed with English history, just talk to Gary Oldman.

After spending three months portraying Winston Churchill for his film “Darkest Hour,” Oldman told TheWrap’s Steve Pond that he dove back in for more of the wartime prime minister by binge-watching Netflix drama, “The Crown.”

But it turns out “Darkest Hour” and “The Crown” have more in common than just their time periods (the former is set in 1940, the latter begins in 1947). As Oldman was reliving post-war Britain, he spotted his “Darkest Hour” co-star Stephen Dillane (Lord Halifax).

“I went, ‘That’s Stephen Dillane! In a scene! With Churchill!’ So I wrote to Stephen and I said, ‘you are a gentleman, because you never ever mentioned or gave away the fact that you worked with another Churchill,'” Oldman said. “And he wrote back, ‘I only work with Churchills.'”

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In “Darkest Hour” Dillane plays Lord Viscount Halifax, one of Churchill’s chief political rivals, but in one episode of “The Crown” he plays the British painter Graham Sutherland.

London-born Oldman didn’t work off the many other on-screen portrayals of Churchill for his own performance, but he did exchange notes with “The Crown’s” own Churchill, John Lithgow.

“I got John’s number and wrote to him and said well done,” Oldman said. “We addressed each other, ‘Dear Mr. Churchill.'”

Watch a clip of Oldman talking about his binge-watching experience above.