Johnny Depp goes carriage-surfing in Pirates of the Caribbean: On Stranger Tides. (Peter Mountain/Disney)

The latest instalment of the Pirates of the Caribbean franchise finds Disney in a difficult place. The adventures of Jack Sparrow (Johnny Depp) and his merry crew have raked in more than $2 billion in box office loot – pretty savvy for a series inspired by a theme park ride. But the last film was a bloated blockbuster with a plot as tangled as Sparrow's gangly goatee.

So it's back to square one, in a sense, for Pirates 4. Gone are the plucky pair of Orlando Bloom and Keira Knightley. Also sent for a long walk down a short plank was original Pirates director Gore Verbinski (who seems to be having lot more fun with animation these days anyway).

The filmmaker at the helm this time around is Rob "Did anyone see Nine?" Marshall. A director with a flair for musicals, he continues the trend of studios parachuting in high-profile faces in an attempt to save a flagging franchise. So what does Marshall offer? Have my dreams of a Pirates of Penzance revival finally come to fruition?

Penelope Cruz joins Johnny Depp in the latest Pirates instalment. (Peter Mountain/Disney)

Sadly, it seems returning Pirates to its roots has turned the blockbuster back into an amusement park ride: a harmless, mildly amusing journey filled with spectacle to spare.

What's new? To replace Knightley, Penelope Cruz joins the fray as Angelica, a former lover spurned by Sparrow. No one can question the female pirate's pulchritude (perhaps filming while pregnant had something to do with her glow), but Cruz lacks the wide-eyed fury Knightley brought to the series.

Another dilemma: just what do you do with demented hero Sparrow, who has been to the ends of the earth and then some? Well, Pirates 4 offers up a search for the Fountain of Youth. Once again there is a map involved, magical items to obtain and a race to win as Spain, Britain and mangy pirates all vie to be the first to taste the eternal spring's rejuvenating waters.

It's classic junk food cinema, filled with massive set pieces, enough CGI effects to power the SETI program for years and a story that will fade faster than morning fog.

All the staples are here: Jaw-dropping scenery? Check (with filming conducted mostly in Hawaii this time around). Drawn-out sword fights? Check. Supernatural scares on the high seas? Take your pick of Blackbeard's possessed pirate ship or murderous mermaids.

Of course, every now and then we all crave excess, so if you do find yourself wading into Pirates 4, here are a few choice tidbits to chew on:

• Don't arrive late since the best sequence happens early on, with Sparrow leading King George's palace guards in a merry chase through London. Depp actually goes carriage-surfing, Teen Wolf-style.
• Speaking of King George, award-winner Richard Griffiths appears as the sputtering, pink-faced monarch.
• Joining the king courtside is Geoffrey Rush, who returns as Barbossa. Turning the ruthless pirate in to an even more ruthless privateer gives the actor a lot to play with. Plus, the image of his weather-beaten mug covered in pancake make-up and rouge is unforgettable.
• Another toughened face, Ian McShane, gets his growl on as the infamous Blackbeard. With his zombified crew, a mystical sword and all sorts of black magic at his disposal, he's more Merlin than marauder. But still it's nice that Sparrow gets a decent opponent.

(A quick aside concerning the action: if you're considering spending your doubloons on a 3D ticket, don't bother. Except for a few thrusting sword tips and spooky faces, the technology is poorly used. With many of the big set pieces occurring at sea on cloudy nights, the most pronounced effect of the 3D glasses is darkening images that are already difficult to see.)

Which brings us back to our boy, Captain Jack. In Hollywood's long history of pirate films, there's never been quite a character like him. When he first flounced onto to the screen, Sparrow was barnacle-encrusted breath of fresh air. Equal parts Douglas Fairbanks and Dean Martin, he was the clown prince of the high seas. You'd think after his successes for Disney, the rapscallion should have earned the right to sail off into the sunset with some woman of ill repute.

But considering the booty On Stranger Tides will likely bring in over opening weekend, Sparrow will inevitably set sail again and again and again.

RATING: Two moldy skulls out of five.

Penelope Cruz, Johnny Depp and Ian McShane in a scene from Pirates of the Caribbean: On Stranger Tides. (Peter Mountain/Disney)