PIRATES OF THE CARIBBEAN: DEAD MEN TELL NO TALES ??????

129 minutes (M)

Five films into the Pirates of the Caribbean series, the truth must be faced: the preening Captain Jack Sparrow, played by Johnny Depp, is just not as charming as he used to be.

Perhaps this reflects Depp's flagging energy, or perhaps there's simply a limit to how long you can sustain interest in a series of fanciful pirate ghost stories inspired by a Disneyland ride.

For a while, director Gore Verbinski kept things going by making each instalment more baroque than the last - a process that culminated in the psychedelic Pirates of the Caribbean: At World's End, which saw Captain Jack confronting dozens of his own doppelgangers while marooned on a desert island.

At a pinch, you could see this as dramatising the psychological conflicts beneath Jack's unfailingly jaunty exterior. In any case, since Verbinski departed the series the character has reverted to being strictly a collection of audience-pleasing effects - mincing, leering, throwing up his hands in mock terror, and generally signalling that nothing will affect him for long.

Essentially Depp has spent the entire saga conspiring with the audience, letting us know it's all just a game. This has a surefire appeal, but also creates a risk: if the main character can't keep his mind on the story, why should we? The question is more pressing than ever now his flouncing around has lost its novelty, with no alternate source of excitement on the horizon.

Directed by the team of Joachim Ronning and Espen Sandberg - Norwegians whose previous collaborations include 2012's Kon-Tiki, an enjoyable true-life sea story - Dead Man Tell No Tales is blatantly a potboiler rather than a film that needed to be made.

At least the script by Jeff Nathanson (Catch Me If You Can) manages to tie up some loose ends from earlier in the saga. Geoffrey Rush resurfaces as rival buccaneer Hector Barbossa, and we learn the fate of Jack's ship the Black Pearl, which he's been carrying round in miniaturised form inside a bottle.

In place of Orlando Bloom and Keira Knightley - the technical hero and heroine of the initial Pirates trilogy - we get Australia's Brenton Thwaites and Britain's Kaya Scodelario as a fresh pair of pretty young things who, perhaps inevitably, prove as bland as their predecessors.

As a dashing sailor in search of his father, Thwaites still acts like the Home and Away hunk he was not so long ago. Scodelario, who was Cathy in Andrea Arnold's version of Wuthering Heights, is a potentially more interesting presence, but she's saddled with the deadly role of a self-taught scientist who shows her intellectual prowess by acting prim and stuck-up.

This may be someone's idea of a feminist statement; if so, it's hard to reconcile with the misogyny on display elsewhere - notably in a mirthless comedy bit where Jack wriggles out of a forced marriage. Penelope Cruz - introduced in the last Pirates chapter, On Stranger Tides, as Jack's female equivalent - is nowhere to be found.

For the usual reasons too complicated to explain, all the lead characters wind up on a quest for the fabled Trident of Poseidon, tangling with a crew of spectral pirate hunters along the way. Javier Bardem plays their vengeful leader, though his performance largely disappears under all the digital effects and Halloween makeup.

Also close to unrecognisable is Paul McCartney, whose cameo as Jack's uncle aims to one-up Keith Richards' appearance in On Stranger Tides - though Richards' involvement made more sense, given how often Depp cited him as a model for Jack's rockstar persona.

The mandatory slapstick action sequences are competently done, especially a bank robbery involving the theft of the entire bank. A handful of quips have a Monty Python flavor: condemned to death, Jack champions stoning as an execution method on the grounds that it "gets the crowd involved".

But there's little of Verbinski's flair for topping one absurdity with another, and it's clear that Ronning and Sandberg are under orders to remain in familiar waters rather than seek out anything new.

It doesn't help that much of the action is shrouded in dreary semi-darkness, especially when viewed through 3D glasses. Considering the vogue for 3D blockbusters has lasted almost a decade, you'd think by now Hollywood would have solved that problem at least.