WHEN, IN 1952, the 23-year- old Ernesto “Ché” Guevara set out to discover Latin America from the seat of a temperamental Norton motorcycle, his experiences during the eight-month journey ignited his idealism. He dreamt of pan-American unity, mutual respect and co-operation within the Latin American countries, filling impassioned pages in his journal on the subject.

It’s appropriate, then, that on a small scale at least his dream was realised when, about 50 years later, his journal was adapted into a film, The Motorcycle Diaries. A Brazilian director, a Mexican star, a co-star from Argentina, a producer from the United States — it truly is a pan-American production. But to describe it thus runs the risk of making this impressive biopic sound dry and worthy when in fact it’s vital and charming and as seductive as the open road.

The Guevara we see on screen (played by the Mexican heartthrob Gael García Bernal) is by no means an exact representation of the Guevara who comes across in the diary. But it is common knowledge that Guevara “polished” his travel journal before its publication; by that time he was on his way to becoming a prominent political figure and might have succumbed to a touch of myth-making.

In contrast to the adventurer in the book, Guevara in the film is well-meaning but gauche; boyishly handsome but plagued by debilitating asthma attacks. He is also compulsively honest, with a tendency to blurt out unpalatable truths, frequently jeopardising his chances of a free meal or a bed for the night.

Guevara’s companion on the trip is Alberto Granado, played with gusto by the Argentinian actor Rodrigo de la Serna. To share screen time with the talented and photogenic Bernal is a challenge for any actor, particularly when the character he plays is not exactly physically prepossessing — in real life, Granado was a chubby, dumpy little man whose legs barely touched the ground on either side of the motorcycle. But Granado had a big personality and it is on this that de la Serna capitalises, giving a charismatic bear-hug of a performance.

The director, Walter Salles (see interview), does a good job of negotiating the potential pitfalls of the subject matter. It is a little episodic — road movies usually are — but the film successfully builds to an emotional climax.

And, while we do get a sense of Guevara’s political awakening, Salles manages to avoid hammering home the spiritual growth of his hero. There are still some lump-in-the-throat moments however, not least the shot at the end of the real Granado, now in his eighties, looking to the horizon in a wordless tribute to the memory of his old friend.

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