Phoenix rises to the role

If you represented a US tourist office, last week might not have been the best time to visit the London Film Festival. Two films - Walk the Line and The King - offered fascinating but hardly flattering views of the American South and West.

It would be hard to make a dull movie about Johnny Cash, but even harder to imagine a better one than James Mangold's Walk the Line, a crowd-pleasing barnstormer of a movie with enough energy to light up the Las Vegas strip.

Mangold paints a portrait of the Man in Black that pays him ultimate respect without ever (or hardly ever) sentimentalising him. The cast is flawless (Dallas Roberts does a wonderful cameo as Sam Phillips), but the film belongs to Joaquin Phoenix as Cash and Reese Witherspoon as his soon-to-be wife, June Carter, both of whom do their own singing.

Phoenix nails the stance, the curledlip delivery and that mix of charm and danger that led MTV to call Cash "the original gangsta", but he also gets the voice, with its sudden drops into a gravelly base register. And Witherspoon is captivating, not just in the singing (which is pitch-perfect) but in capturing the contradictions of a woman from a strict, Southern baptist tradition growing up in the permissive Sixties.

The King, from British director James Marsh, is very different: a southern Gothic tale that slips slowly but effortlessly into violence.

The screenplay by Marsh and Milo Addica (who, on the basis of Monster's Ball and Birth, is staking his claim to be a chronicler of America's weirder side) is about a young man called Elvis who turns up in Corpus Christi, Texas, and relentlessly insinuates himself into the life of a bigoted, charismatic preacher (William Hurt, excellent).

It's like Patricia Highsmith meets Night of the Hunter, and you can't take your eyes off Gael Garcia Bernal as Elvis. By turns charming, vulnerable and vicious, he almost - but not quite - makes you understand why the family takes him in. Marsh may not entirely pull off the film's central gamble, but he gives you a dark and fascinating run for your money.

Walk The Line
Cert: 12A