There's no 13 in Ocean's Thirteeen. Ocean's Twelve dutifully complied with the arbitrary rule that sequels are their predecessor plus one, throwing in Julia Roberts as the reluctant ad hoc recruit. Instead of really using her, though, it was a long set-up to a meta-joke about stardom, as Tess ended up impersonating "Julia Roberts." But as Ocean's Thirteen opens, neither Roberts nor previous addition Catherine Zeta-Jones are in attendance. "It's not their fight," George Clooney explains, and the crew is back down to the core. Andy Garcia eventually becomes number 12, but I guess Ocean’s Alternate Twelve wasn’t an option.

I'm not sure that any of this matters, but part of what's great about Ocean's Twelve was how it cheerfully acceded to the absurdity of the numbers rule and added a gang member without really caring. Ocean's Thirteen is grimmer, more dutiful and plot-driven, as functional as its purely place-holding title. Regardless, it's also one of the weirdest movies of Steven Soderbergh's already bewildering career.

As the film opens, elder member Reuben Tishkoff (Elliott Gould) lies unconscious and slumped over in a hospital bed, the gang surrounding him. The first two installments made a virtue out of weightlessness; every seeming injury, setback or arrest was all part of a ridiculously airtight plan. In Ocean's Thirteen, actions have consequences; Reuben's will to live has been destroyed by the betrayal of would-be casino partner Willie Bank (Al Pacino). The two were supposed to be co-partners in the opening of Bank's newest venue, Bank, but having drained Reuben of his usefulness, Willie casts him aside. "You shook Sinatra's hand," a bewildered Reuben sputters and collapses. The gang sets out to exact revenge on a colossal, bankrupting scale.

The odd taint of real-world gravitas lingers throughout Ocean's Thirteen, making a previously ebullient franchise weightier, or at least more ponderous. The first hour is mostly garbage, a laborious exposition machine that no amount of typically stylish lensing or editing can conceal. Midway through, something happens: Rusty (Brad Pitt) knocks on Danny's (George Clooney) door. A sniffling Danny says he was just eating a pepper, but he's been watching Oprah. As Rusty and Danny watch, Oprah unveils 12 new beds and a new house for a struggling family. Rusty and Danny sniffle, then move on with their planning.

The joke turns out to be anything but a one-off, and the payoff an hour later is totally worth the wait -- especially since Ocean's Thirteen turns out to be a lot of fun (if not as exclusively as the first two films) once the groundwork is laid. But the joke -- how the plight of poor kids can move anyone, even presented in the most bathetic way -- seems to be a cover for something else. Consider: Two of Soderbergh's best films (Bubble and Erin Brockovich) examine poverty minutely, documenting life on the very bottom rung of the economic ladder. There's obviously a beating, socially active heart somewhere in there, and while Ocean's Eleven and Twelve positively reveled in the expensive clothing and accessories in every scene, Thirteen foregrounds the frivolity of the enterprise. It's not just the final gag; there's a bizarre subplot where Virgil (Casey Affleck) and Turk (Scott Caan) lead Mexican factory workers in a Molotov-cocktail throwing strike for wages. It's not part of the plan, and almost derails the heist, but Virgil's conscience won't let him rest – acting much as the sub-plot does within the movie itself. It's a rare non sequitur in a movie with no use for them (unlike its predecessor), hard to explain without thinking of the movie as inexplicably concerned with social injustice and seemingly somewhat disgusted with its own frivolity. Considering that Soderbergh's next project is a two-movie biopic on Che Guevara -- and that the gag suddenly brings the movie to life -- it doesn't seem too far out.

Oh, right. So, is the movie actually any good? Sort of. Soderbergh's at the top of his technical game as per usual, but he can't overcome a script that's simultaneously streamlined and clunky. Bizarrely, Clooney and Pitt are pretty much relegated to the sidelines. Much of the capable cast have only the most token of appearances; everyone gets equal time, but no one seems to get enough (especially personal fave Scott Caan). The exceptions are Gould and Carl Reiner, emphasizing mortality throughout. (Oddly, villain Pacino gets more screen time than anyone, delivering his first decent performance since The Merchant of Venice three years ago.) The sharper jokes fade away in the melancholy finale, a surprisingly elegiac ending to a movie (and possibly a franchise) that's ostensibly built on never getting in too deep. Mainstream audiences will probably groove on it more than the predecessor -- there's definitely a plot to latch onto, so sniping about the previous installment’s nonsensical nature should fall away. But Ocean's Thirteen is ultimately a regression for the previously fun-loving series.