The success of 2003's "Pirates of the Caribbean: Curse of the Black Pearl" was found in its gonzo Saturday matinee appeal. Determined to keep itself as frothy as possible and as thrilling as summer entertainment allows, "Black Pearl" was an enormous, and unexpected, sensation at the box office. More importantly, it made audiences slap-happy again with the idea of seeing pirates onscreen.

"Dead Man's Chest" is the hotly anticipated second installment (a third, "World's End," is due next May), and it gives the audience what it wants, but this time the attitude feels deflated, and the end product lacks a good sense of rum-drunk playfulness.

"Black Pearl" had a stealth appeal to it that was irresistible: audiences weren't expecting quality from a movie based on a theme park ride, they didn't believe a pirate movie could be so richly pleasurable, and nobody had seen Johnny Depp take such a mainstream acting risk before. That sparkling element of surprise helped the film hurdle some serious comedy problems and third act pacing issues. "Chest" launches itself under intense expectations, and you can sense the production is now wary of taking on any new gambles with this enormously budgeted sequel.

Director Gore Verbinsky is more than happy to dish out additional Jack Sparrow escapades, and for the most part, this is a slick motion picture. Using his bottomless buckets of money to dream up sophisticated action set pieces for his characters to tumble around in, "Chest" is spectacular when the adventure goes huge. For instance, not only do Jack, Will, and Norrington finally have their much-anticipated battle of wits and steel, they just happen to be clashing on top of a gigantic rolling water wheel, scrambling to keep their balance as they truck down a jungle mountainside. Also great fun is the Kraken: Davy Jones's monster squid-like "pet" that inhales entire ships in one gulp on command. Verbinski devotes nearly 30 minutes to fighting this beast, but it's worth the excessive screen time; it's an astounding sea creature special effect and the film's one viable threat (out of far too many) to our heroes.

Filming sequels back-to-back always seems to freak out filmmakers, pushing them to cram in enormous story lines (look to the "Matrix" and "Back to the Future" films for further proof of this phenomenon) out of fear there's not enough to sustain two movies. "Dead Man's Chest" is no exception. In retrospect, "Black Pearl" felt simplistic and easygoing, while the sequel seems leaden and distended by the sprawling story it wants to tell. "Chest" spends an inordinate and punishing amount of time with expository dialog, stealing the life from the characterizations, and leaving little room to play outside of the requisite massive action sequences. Things are so suffocating and knotty, Verbinski stops the film mid-way to afford pirate scallywags Pintel and Ragetti the chance to explain the plot to the weary audience.

In separating the characters this time around, "Chest" is not lacking diverse plotlines, but it has difficulty keeping the story in sync, forgetting to make room for organic joviality and some snappy patter between characters. The picture starts to wear down with each new plot twist, and it's hard to ignore that no matter how fancy and thoroughly realized the new characters are (Davy's sea-encrusted thugs are something to behold), the story has the tendency to come off as a droning rehash of the first film.

Whenever "Black Pearl" stalled, it had Johnny Depp to kick on the lights again. In "Chest," Depp's playfulness is amped considerably, but so is his self-awareness. It's still a mischievous, jolly bit of acting, and Depp appreciates what people want from his performance; however, he rings the bell one too many times. Sparrow hasn't worn out his welcome yet, but Depp teeters on self-parody at times, almost coming off as a class clown Jack Sparrow impression rather than the real thing that electrified the first film.

Faring much better is Keira Knightley, here given the most substantial growth of the three leads. In "Chest," Swann gets her prized moment to join up with the pirates, and with it is born a more impassioned and assured performance from the actress. While the boys slosh around in their established personalities, Knightley gets to play it all: sexy, feisty, and heroic.

As "Chest" heads into the final lap of its 150-minute running time, Verbinsky lets the action take the reigns for an extended climax that serves more as an elaborate set up for the next film than a satisfying closure to this one. Suffice it to say, the last shot of "Dead Man's Chest" is absolutely killer – we're talking a "Batman Begins" level of sweetness - and blows the door wide open for "World's End" to ditch the unmanageable plot wrangling and return this franchise to the flume ride exuberance it once had.