Based on Barry Levinson's 1988 film, there’s no doubting Rain Man’s cinematic pedigree. Barry Morrow’s screenplay won one of four Oscars, while Tom Cruise and Dustin Hoffman gave highly memorable performances as two brothers embarking on life-changing journeys – Cruise delivering an incendiary portrayal of self-centered, money obsessed Charlie Babbitt; Hoffman scene-stealing as Raymond, the autistic savant brother Charlie never knew he had until their father dies, leaving Charlie a nothing but a rose bush and a vintage Buick and Raymond the family fortune.

Dan Gordon’s stage adaptation, skillfully directed by Terry Johnson on a series of sliding, sparsely furnished sets, teams Hollywood stage virgin Josh Harnett with vastly experienced British actor Adam Godley as the Babbitt boys and wisely steers clear of replicating the central road movie structure of the movie, in which Charlie kidnaps his institutionalised Raymond and whisks him off to Los Angeles to grab a share of the inheritance, focusing instead on the almost impossible relationship between long-lost blood brothers who share the same gene pool but inevitably communicate as if they are from different planets.

Hartnett acquits himself surprisingly well in his stage debut, but it’s a pity that he tends to shy away from depicting the stormy side of Charlie. This amoral character’s internal tensions surely ought to mirror Raymond’s compacted emotions and his journey of self-discovery from cynical money-grabbing chancer to reaching a level of adult maturity through the reconciliation with his disconnected brother just isn’t given enough mileage.

Even so, as Raymond, Godley creates an extraordinary sense of heart-wrenching empathy in his pitch-perfect evocation of a socially disabled man capable of astonishing feats of memory – like learning the entire A to J section of the phone book at a glance – but who lives in a routine-obsessed world of unfathomable loneliness where Judge Judy and TV quiz shows are his best friends. There’s a surprising amount of laughter in Godley’s enthralling performance too – Raymond’s monotone mantra “I don’t know” turns into a kind of running gag and there’s some terrifically funny dialogue which sees fuming Charlie and straight-faced Raymond almost turn into a smart guy-dumb guy comedy double act.

It’s not long before both actors wipe away memories of Cruise and Hoffman. But it’s Godley’s unforgettable pin-drop scenes which stands out and may well leave you reaching for the Kleenex, especially during the final moments when it begins to sink in that Raymond has managed to survive outside his care home, togged himself up in a smart suit, learned to dance with a hooker and even kissed a girl (Mary Stockley making the most of the thankless role of Charlie’s girlfriend, Susan), but will never be capable of a ‘normal’ relationship with his brother or anyone else. Odd tears running down cheeks and audible “Aaahs” from the audience when Raymond tentatively reaches out to touch his brother for the first time in decades suggest that Rain Man on stage hits all the right emotional buttons and is more than just another West End screen-to-stage hybrid.

- Roger Foss