1 of 2 | Peter McDonald and Paul Rudd star in "Power Ballad," which is now playing in theaters and on video-on-demand platforms. Photo courtesy of Lionsgate

NEW YORK, June 28 (UPI) -- Once and Sing Street writer-director John Carney's new music dramedy, Power Ballad, explores how one hit song completely changes the lives of former boy band member Danny (Nick Jonas) and struggling wedding singer Rick (Paul Rudd).

Peter McDonald co-wrote the film and plays Sandy, Rick's band-mate and loyal best friend, who stands by him when he claims he helped write one of the most famous songs in the world.

The movie is now playing in theaters and available on pay-per-view platforms.

"This is one of the themes of the story -- what do you define as success for yourself and what would you do to achieve it?" McDonald, 54 told UPI in a recent Zoom interview.