Actors Johnny Depp (L) and Penelope Cruz are shown in a scene from the film "Pirates of the Carribean: On Stranger Tides" in this undated publicity photo released to Reuters April 27, 2011.[Photo/Agencies]

At two hours and 16 minutes, "Pirates of the Caribbean: On Stranger Tides" — the fourth film in the ridiculously successful Disney franchise — is the shortest in the series. But it still feels overlong and overstuffed: needlessly convoluted yet, at the same time, phoned-in.

And the fact that this one's in 3-D — because everything's in 3-D, silly thing — does nothing to liven up the action. Those three-dimensional digital effects mainly consist of various swords and snakes and such being flung at our faces.

Boo! Did you jump?

That's not to say this summer behemoth doesn't have its thrilling moments. Rob Marshall ("Chicago," "Nine") takes over for Gore Verbinski, who directed the first three "Pirates" movies, and his knack for choreography comes shining through in individual set pieces. An early chase sequence, in which Johnny Depp as the randy Capt. Jack Sparrow escapes the clutches of the puffy, bloviating King George II (Richard Griffiths), is expertly staged. Jack swings from chandeliers and hangs from ropes, straddles moving carriages and steers a cart full of flaming coal, and we're right there alongside him every breathless step of the way.

Similarly, a nighttime attack by mermaids — beautiful, seductive, deadly mermaids with razor-sharp teeth — provides a jolt. Because what's hotter than mermaids, except maybe naughty vampire mermaids? And the first time Jack crosses paths (and swords) with his old flame Angelica, played by a spirited Penelope Cruz, it's in a lengthy, fluid battle across beams and atop barrels. (Oddly, Cruz and Depp, who co-starred together in 2001's "Blow," don't have a whole lot of chemistry once they have to actually stop and talk to each other.)

It's everything that happens in between, all the chatter and the exposition, that make the latest "Pirates" such a repetitive bore.

Depp's performance, which seemed like such a free, goofy, inspired bit of work when the first film came out back in 2003, now feels so dialed-down and obvious, it's as if he could do it in his sleep. With the (unexplained) absence of Orlando Bloom and Keira Knightley this time around, Depp's Sparrow is now front and center — he's almost the voice of reason — rather than the bejeweled and eyelinered clown riffing in the corner, commenting in the action.

As for the plot — not that it matters, really — this time the script from Ted Elliott and Terry Rossio centers on a search for the fabled Fountain of Youth. Jack has no ship anymore, so when Angelica kidnaps him and drags him aboard the Queen Anne's Revenge, the ship belonging to the fearsome Blackbeard (a constrained Ian McShane), he's stuck going along for the ride.

Blackbeard seeks the fountain after receiving a prophecy that he's going to die in two weeks. But the Spanish are after it, too. And so are the English, led by Jack's deceitful old nemesis Barbossa (Geoffrey Rush).

Did we mention that there are zombie pirates aboard Blackbeard's ship? The fact that they're zombies makes no sense at all — I mean, come on, wouldn't they be trying to eat the brains of the living pirates at every opportunity? — and feels like yet another attempt to inject arbitrary weirdness in the place of genuine inspiration.

Also on board is a hunky man of faith with just the right amount of facial scruff named Philip (Sam Claflin), who falls for one of the mermaids (Astrid Berges-Frisbey), who's been taken prisoner because her tears are required to activate the Fountain of Youth waters. (Don't ask.) Ostensibly, this relationship is intended to replace the young-people-in-love subplot that Bloom and Knightley provided, but it's so full of banal angst, it feels a little too much like something you'd see in the "Twilight" series.

But surely that's coming in the fifth Pirates movie: sexy werewolves.

"Pirates of the Caribbean: On Stranger Tides," a Walt Disney Pictures release, is PG-13 for intense sequences of action/adventure violence, some frightening images, sensuality and innuendo. Running time: 136 minutes. One and a half stars out of four.