This superb biopic of Brian Wilson, the troubled musical genius behind 1960s pop icons The Beach Boys, takes a radical approach to what is often a highly conventional genre, casting two very different actors to play its protagonist at two contrasting stages of his life and shuffling the narrative back and forth between them.

It is a risky strategy, but one that pays off handsomely in Love & Mercy thanks to compelling dual performances by John Cusack and Paul Dano.

Dano is the brilliant young Brian of the 60s, beset by his domineering father Murry but pushing the envelope of pop music as he steers the band far beyond their surf-rock origins to create such groundbreaking songs as ‘Good Vibrations’ (his ‘pocket symphony’) and ‘God Only Knows’.

 

 And Cusack is the damaged 1980s Brian, his mental health wrecked by drugs and nervous breakdowns, and in thrall to another abusive father figure, his manipulative therapist Dr Eugene Landy (a creepy Paul Giamatti), who has turned him into a heavily medicated recluse.

Love & Mercy is fascinating when it takes apart the nuts and bolts of Wilson’s songs, showing how he used the music studio as his instrument while striving to outdo The Beatles in harmonic daring. But equally impressive is the way the film convinces us of Brian’s hard-won redemption and recovery after he meets model-turned-car dealer Melinda Ledbetter, played with grace and grit by Elizabeth Banks, the woman who rescued him from Landy and became his second wife.

Certificate 12. Runtime 121 mins. Director Bill Pohlad

Love & Mercy is released on Blu-ray & DVD on Monday 4 January by Sony Pictures Home Entertainment