Paul Rudd plays a closeted spy in the upcoming film The Catcher Was a Spy.

The film, from director Ben Lewis (The Sessions), premiered Friday at the Sundance Film Festival in Park City, Utah.

Based on the 1994 biography The Catcher Was a Spy: The Mysterious Life of Moe Berg, the film tells the true story of Moe Berg (played by Rudd), a big-league catcher who became a spy for the United States during World War II. Berg's mission was to stop German scientist Werner Heisenberg (Mark Strong) from building an atomic bomb for the Nazis.

Berg spoke nine languages and graduated from Columbia Law School.

“It’s a crazy story and it’s a true story, and he really is one of the more fascinating figures I’ve ever read about,” Rudd told Deadline Hollywood from Park City. “I read this script a while ago and I never forgot about it. I knew nothing about Moe Berg, but I can’t believe he existed, and the opportunity to try and discover something about the guy was absolutely appealing.”

According to several reviews, the film mostly keeps its distance on the topic of Berg's sexuality, only offering hints that he might be gay.