Film review: Begin Again (15)
Actors secretly harbour a dream to be a musician and musicians want to be an actor one day." So says Brit James Corden, who turns up in this love song to the power of music which is heaving with job swappers.
CeeLo Green, Mos Def and Maroon 5's Adam Levine learn their lines while Keira Knightley warbles (not too shabbily) and Hailee Steinfeld wields a mean axe.
Behind all this music and mayhem on the streets of New York is Dublin director John Carney whose 2006 film Once became an indie, then mainstream, hit.
He repeats the trick here (it could be called Once Again) with a similar tale of two lost souls who find each other and then redemption through riffs, laughs and earbuds.
Washed-up producer Dan (Mark Ruffalo) has lost his family, his job and his mojo. He still wants to "invest and nurture" acts in an age of disposable pop. Songwriting sparrow Gretta (Knightley) splits with boyfriend Dave (Levine) who has fallen for the rock'n'roll lifestyle (and chicks).
An open mic night brings Dan and Gretta together. Earnest about "authenticity" they set about recording her album on the streets of New York. This is "let's-do-it-right-here" the movie.
Putting Knightley and Corden in the same film is rather like putting a chocolate topping on a box of puppies but Ruffalo is a superb counterbalance, keeping it the right side of grating with his underplayed passion and world weary chic.
The film is packed with puckish charm, insider knowledge and rough 'n' ready whiz. The sequence when Dan pictures a musical arrangement Mary Poppins style - with the instruments playing themselves - is, unavoidably, a delight.
And if it's just a little smug and preachy, then the music is enough to inject joy into the most downbeat of souls.