Before he was fighting demogorgons on Stranger Things or playing Santa Claus in Violent Night, David Harbour was in a movie directed by Madonna.

Appearing on Jimmy Kimmel Live! on November 30, as reported by Yahoo, the actor shared the “cloak and dagger experience” of being in Madonna’s directorial debut and how he came to be cast. The film, W.E., which was also co-written and co-produced by Madonna, tells the story of a young woman in 1998 (Abbie Cornish) who becomes obsessed with an affair from the 1930s between King Edward VIII and American Wallis Simpson. It also stars Oscar Isaac, James D’Arcy, and Natalie Dormer, among others.

When asked how he became involved in the film, Harbour recalled being told by a casting director to head to a top-secret read through for an unknown project, because “the director really liked you in this movie Revolutionary Road, you have like a sex scene in it” and “they thought you were sexy.” With no clue that Madonna was the director, all weekend, “I literally was thinking about Ridley Scott and like Martin Scorsese,” assuming he was sexy enough for the role. But when she walked into the read-through, the first thing that came over him was, “wow, Madonna thinks I’m sexy.” The feelings were mutual, as Harbour was immediately reminded of watching the “Open Your Heart” music video as an eleven year old boy and crushing on her.

Working with the singer-as-director turned out to be a bit difficult. “She is a genius in many realms,” he said, before describing how she would come in right before a shoot and completely change up a dance number. While W.E. turned out to be a box office failure (it did get nominated for Best Costume Design at the Academy Awards), Harbour did get a lot out of it, even scoring an invite to her birthday party in London. “It was one of the coolest things I’ve ever done in my life,” he said. “I danced with Madonna to Madonna music.” We’re glad that he at least got her to “open [her] heart” to him.