Paul Dano as the young Brian Wilson in Love and Mercy.
The musical biopic has become a formula. A kind of last rites for the greats.
While for pop's long-term survivors, the rockumentary has become another way to resell a glorious past.
The story of the Beach Boys has had both over the years. The saga of the band formed around the three Wilson brothers, who became America's candy-striped answer to the Beatles, has had the telefeature and mini-series treatment in the past.
So what more could Love and Mercy, a movie that focuses solely on Brian Wilson, the band's primary songwriter and pioneering producer, add?
There have been plenty of declarations of Brian Wilson's pop genius. This is both explanation and exploration of it.
It might be a musical biopic but it sidesteps formula with a split narrative - one in which Paul Dano plays Wilson in the 1960s as he reaches his artistic peak, then freaks; the other with John Cusack playing Wilson in the 1980s when he's creatively spent and under the dominating care of psychologist Eugene Landy.
No Cusack doesn't much look like Wilson, or like Dano 20 years on. But the performances of both actors, plus the deft way Love and Mercy switches between the two eras makes this an affecting portrait of the man and his times.
No it's not much of a Beach Boys chronicle - other than Mike Love, portrayed as the chief naysayer to Brian's artistic ambitions, the other members of the group aren't much differentiated.
And the brothers' father, Murry, who managed the band until he was fired then sold off his sons' song rights for a fraction of their potential worth, has his reputation as a manipulative abusive bully enhanced by his depiction here.
Though the most telling scene in that relationship isn't a shouting match - a slowly panning camera finds Dano's Wilson alone at the piano, gingerly working his way through the angelic melody of God Only Knows, eventually bringing a scowling Murry into shot who dismisses the new song: "I don't much care for it ..."
But much of the film's 1960s episodes also crackle with creative energy. The scenes with Dano's Wilson on an extended high in the studio in the sessions for Pet Sounds and the aborted Smile album are full of magic moments.
When Wilson is explaining to the session players of the Wrecking Crew the harmonic inventions of his increasingly ambitious pop songs, this becomes an enjoyable portrait of the artist in his element.
But it can be a little clumsy as a music history lesson too.
It's Brian's first wife, Marilyn, who delivers the line about the Smile album being his "teenage symphony to God" rather than making the man who actually uttered it, deliver the line and come off, well, crazy.
Another of the Beach Boys gets the job of quoting Paul McCartney's view on God Only Knows as being the "best song ever written".
But if there is a surplus of rock history footnotes finding their way into the dialogue, Love and Mercy still delivers something rare in music biopics -- why the music sounds the way it does and how Wilson, on the likes of Good Vibrations, used the studio itself as an instrument.
But at some point Wilson's mental illness, possibly exacerbated by his drug intake, left him in the care of Landy.
That's until he was rescued by his future second wife, Melinda Ledbetter (Banks), a car saleswoman he met while out shopping for a new Cadillac.
The 80s half of the movie doesn't ring quite as true as the 60s one.
For one thing, Giamatti's performance as the controlling Landy gets fairly close to caricature and how Ledbetter takes on the psychologist to free Wilson from his clutches feels a little too tidy.
Still, there's plenty of charm in how Wilson, a heavily medicated man barely coping with the outside world, courted Ledbetter, and Banks and Cusack have considerable chemistry together.
If their part of the movie feels like the authorised version of the Brian Wilson story, that's okay. Together, the two timelines of Love and Mercy work in deft harmony, resulting in one of the most fascinating musical biopics in years.
Cast: Paul Dano, John Cusack, Elizabeth Banks, Paul Giamatti Director: Bill Pohlad Rating: M (drug use and offensive language) Running time: 121 mins Verdict: Compelling look at the troubled talent behind the Beach Boys