Ang Lee’s psychedelic romp Taking Woodstock is a film of contradictions. Despite its sprawling cast of hirsute and predominantly naked extras, this is ultimately a small-scale family drama that just happens to take place against the backdrop of one of the defining moments in America’s pop cultural history. It’s a film about a famous rock festival in which music takes second billing. It’s a movie that wears the trappings of the countercultural movement like bunting, yet is essentially mild-mannered and rather conventional.

That’s not to say that Taking Woodstock is not an enjoyable movie, just that, unlike the event in 1969, it is not likely to secure a lasting place in the collective consciousness.

The comedian Demetri Martin acquits himself well in the central role of Elliot, the dutiful and long-suffering son of Mr and Mrs Tiber (Henry Goodman and a riotously funny Imelda Staunton). Elliot is the archetypal nice Jewish boy. Clean-cut in chinos and sports shirt, he’s the antithesis of the marauding bands of fringed and beaded dropouts who are roaming the country. He lives in a buttoned-up backwater of a town in New York State; it’s no surprise that the family business — a flyblown motel that is optimistically described as a “summer colony” — is struggling.

Elliot spots an opportunity to boost local commerce when he reads about a rock festival looking for an alternative location. One life-changing phone call later and Woodstock has found a new home.

Elliot finds himself persona non grata with the locals and a nasty undercurrent of anti-Semitism bubbles to the surface. But that doesn’t stop even the most vociferous of the festival’s naysayers from milking the visiting hippies for every last cent.

Several sequences are inspired by scenes in the famous Woodstock documentary; mud-sliding and face-painting abound. The screenplay meanders between iconic images, wandering aimlessly and amiably like a stoner’s anecdote. We witness the wonderful chaos through Elliot’s eyes — he’s an outsider, fascinated and seduced by the free-living flower children.

A colourful array of larger-than-life characters descends on the summer colony. As a distinctively attired security consultant, Liev Schreiber is a hoot even in a role that feels a bit deliberately quirky; but Emile Hirsch’s strung-out Vietnam veteran is curiously peripheral and underpowered.

Elliot and his parents are enriched by these visitors, both spiritually and financially. But will it be enough to prompt Elliot to break away and live his own life? And will his parents ever accept that their son is gay?

The tone is feel-good through and through, so don’t expect too much emotional trauma in Elliot’s journey. It’s photographed lovingly in sun-drenched colour and the scale of the re-creation is genuinely impressive but the film’s main problem is that it lacks a sense of purpose.

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