Robert Pattinson smiles. In fact, he smiles and laughs a lot. In this occasionally rather dark, period romantic drama, set during the Great Depression, he plays a vet who runs away to join the circus and he can't seem to stop chuckling.

It's as if he can't contain his joy at having slipped away, if only temporarily, from the shackles of playing Edward Cullenhands in Twilight.

This week was supposed to see the release of The Tree Of Life, the long-awaited film from Terrence Malick. But that seems to have fallen through because of a distributors' dispute about releasing it pre-Cannes.

Watching this, I couldn't help thinking about what Malick might have made of it.

The plot is like big top Days Of Heaven, while the lead character, Pattinson's Jacob, is a very Malick-like creation, being a Depression-era wanderer who remains immaculately groomed despite all his privations.

Watching him here, you think that there may actually be some future for him beyond the talcum powder complexion and the quiff. He always came across as something of a plank in those films, little more than a supporting structure for the hairdo, but he makes a rather respectable human being in this.

Taken from a bestseller by Sara Gruen's novel, the basics of the tale is another love triangle. After a tragedy leaves him penniless, Jacob jumps on a train and into a career as the vet and elephant handler for The Benzini Bros circus. He also finds himself coming between the star performer Marlena (Reese Witherspoon) and her husband, the circus's tyrannical owner August (Christoph Waltz).

Waltz is great to watch here. He seems to resemble a compendium of every Rob Brydon impression during The Trip. he's taken little bits of all the classic Hollywood crazies but he still seems like a fresh act. Stuck between them is Witherspoon who never really convinces as the glamorous queen of a circus.

You'd need a visionary director to do justice to the slightly surreal nature of life aboard the circus train, where surplus staff are red-lighted (thrown off the train) during overnight journeys.

Francis Lawrence isn't a visionary but, as in I Am Legend, he seems to be developing the happy knack of making films that are just a little bit better than you expect them to be.

Water For Elephants (12A)

Director: Francis Lawrence

With: Robert Pattinson, Reese Witherspoon, Christoph Waltz, Jim Norton, Paul Schneider and Hal Holbrook

Length: 116 mins

***