Keira Knightley Jams With Adam Levine And CeeLo In 'Begin Again' Trailer

Mark Ruffalo and Hailee Steinfeld also star in the 'Once' director's new movie.

Based on the new trailer, "Begin Again" is basically "Once," plus much more famous people.

The similarities between the Keira Knightley and Mark Ruffalo movie and the Irish indie charmer aren't a coincidence though. John Carney directed both, and he's following up his Oscar-winning debut with another musically themed romance.

"Begin Again" (formerly called "Can a Song Save Your Life?") tells the story of Dan (Ruffalo), a down-on-his-luck record producer that loses his job and then stumbles on the untapped talent at an open mic night. The singer he finds is Gretta, played by Knightley, who after going through a breakup with her rock star boyfriend (Adam Levine) turns her heartbreak into music.

In the tradition of "Once," the duo pairs up to create a record. Dan uses his experience as a producer to bring Gretta's music to life in a unique way. He insists that they record the album all over New York City, a different location for each song.

Did I mention that some of the casting appears to have been done during a taping of "The Voice"? In addition to Levine, fellow mentor CeeLo Green appears in a role. I'm assuming that Blake Shelton and Christina Aguilera aren't down for surprise cameos, but I guess you never know.

Back when it was called "Can a Song Save Your Life?" at the Toronto International Film Festival, "Begin Again" charmed audiences and secured distribution from Weinstein not long after its debut.

"Begin Again" is now set for a summer release on July 4.