Usually expectations for part four of a film series would be minimal but the previous two instalments were so poor that the idea of Jack Sparrow returning with a few new faces and a new hand on the tiller makes it feel more like a re-boot than a tired cash-cow sequel.

By the time he had finished the back-to-back shooting of parts two and three, director Gore Verbinski seemed to have been driven half mad by the process – instead of a jolly tale he hectored audiences with some twisted incoherent ramblings.

Song and dance man Rob Marshall (Chicago, Nine) seems to herald a much cheerier disposition. The opening section in London is full of life and fun with a thrilling escape sequence and some top notch cameos. Some of the gags and routines are older than the music hall but that's rather charming.

The film at least remembers to keep Johnny Depp centre stage. The most successful actor of the last decade had been box office poison for a decade prior to the first Pirates. He owes Sparrow and plays him with enough zest to suggest it hasn't yet become a tired financial obligation.

What a creation. Audiences love him almost regard- less of the movie. He is al- ways fun but rarely funny. During the film I kept trying to work out who this scurvy debauched knave with his incongruous burst of florid eloquence reminded me of. Halfway through it hit me: Jack Sparrow is basically Russell Brand's whole act done with a gravely voice.

After a perky start, the picture quickly starts to drag. There's no real plot just a vague outline about discovering a fountain of youth. Sparrow is so watch- able that the Pirates films should be like modern day versions of Hope and Crosby's Road movies. But for some inexplicable reason they feel the need to make them dark epics – no fun.

There are some good moments especially a terrific, scary mermaid attack but a lot of it just seems to be ambling along for no clear purpose and it all gets a bit dull.

On Stranger Tides is better than the previous two films, but it is also considerably smaller.

At World's End was an abysmal folly but it was at least a huge, expensive abysmal folly and the closing battle in a whirlpool was spectacular.

Scaling it back was surely the right thing to do but audiences may suspect that they are trying to do it on the cheap. On a related subject the occasional 3D augmentation is a total gyp: apart from the odd pointing sword it makes little difference – a lot of it isn't 3D at all.

Pirates Of The Caribbean: On Stranger Tides (12A)

Director: Rob Marshall

Starring: Johnny Depp, Penelope Cruz, Geoffrey Rush, Ian McShane, Kevin R. McNally.

Length: 136 mins

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