This light rom-com with (mostly) great music and (mostly) good-looking people has a couple of surprises. (These are not significant spoilers, so read on.) First, Keira Knightley is a decent singer. And, second, the relationship between her character and Mark Ruffalo’s does not go the way one might expect.

Greta James (Knightley) is the tag-along girlfriend of singer Dave Kohl (Adam Levine). She accompanies him to NYC to kick off a new record deal. Dan (Ruffalo) is a record company exec who has lost his mojo—he can longer launch a hit artist. He hears Greta sing and wants to record her music.

Dan is estranged from his wife Miriam (Catherine Keener). When Dan meets Greta, she has just left Dave after watching his reaction to a newly recorded song he plays for her. (She intuits that he has cheated on her while recording in LA.) So the scene is set for them to hook up, no? No. Both are focused on the music. (Although some of their time together is a bit flirtatious.)

Dan comes up with the idea to record Greta’s songs all around New York. Get a couple of good mikes and a laptop and go. Outside. On sidewalks. In alleys. In subway stations. Sidemen include Greta’s friend Steve (James Corden) and Mark and Miriam’s daughter Violet (Hailee Steinfeld).

Dan is old school. An early scene in the film shows him listening to CD’s by new artists while driving through Manhattan. Most are generic rhythmic pop. Dan is so disgusted by what he hears, he tosses most of them out the car window.

Adam Levine of Maroon 5 (and “The Voice” TV show) is a passable actor and is the movie’s best singer. Another Voice star Cee Lo Green has a small part in the film.

Begin Again is an R-rated movie that could easily have been rated PG-13, except for some bad language. There’s no sex, nudity or drug use. Why would writer/director John Carney (creator of the beloved 2006 film Once) feel the need to keep his movie off-limits to romance-minded teens?

Knightley and Ruffalo are fun to watch together. Begin Again is not a typical musical, but music is central to the film. There’s much to enjoy here.