The former Boardwalk Empire star was in the audience at Joe's Pub when he decided to step up and show off his musical skills.

"During Margot's rendition of (James Taylor's) Shower the People, he was moved to jump onstage, hug her and lead the crowd in a chorus," a source tells the New York Post's Page Six.

Actor Paul Giamatti and former Hamilton star Anthony Ramos were also in the audience for the show. Ramos also reportedly teamed up with the singer for a duet later in the evening.