Having missed the first "Night at the Museum" movie — willfully, I'm afraid — I was surprised by how funny and well-made the sequel is, especially for a "family film." "Battle of the Smithsonian" is packed with set-piece scenes of a sometimes uproarious nature and intricately constructed digital action sequences. (In fact, truth be told, the movie has a little too much going on.) And the star, Ben Stiller, who doesn't always rub everybody the right way, is shrewdly positioned here: Apart from a few snappy spotlight moments (a mad verbal wrangle with Jonah Hill as a dim museum guard, and a Three Stooges-style slap-down with a couple of monkeys), Stiller generally — and generously — functions as a traffic cop amid a swarm of sharp comics, including Amy Adams at her most adorable and the great Hank Azaria at the top of his game.

The movie, once again directed by Shawn Levy, is set two years after the events of the first film, in which, as those who saw it will recall and those who didn't can Google, Stiller's Larry Daley took a job as a night guard at New York's American Museum of Natural History and discovered that an Egyptian artifact called the Tablet of Ahkmenrah was bringing all the exhibits to life after hours. In "Battle of the Smithsonian," Larry has become an infomercial star peddling such late-night schlock as super-big dog bones and unlosable key rings on TV. During a sentimental visit to the museum, however, he discovers that the place is being hyper-modernized — it's going interactive and virtual and whatnot — and that all of its musty old real-world treasures are being shipped to Washington, D.C., to be consigned to deep storage at the Smithsonian Institution. Since some of these unwanted items — like the miniature Roman noble Octavius (Steve Coogan) and cowboy figurine Jedediah (Owen Wilson) — are old friends, Larry is alarmed. And when he learns after the relocation that the Tablet has gone missing, he flies down to the capital to help avert a supernatural crisis.

Briefly, a lisping Smithsonian pharaoh called Kahmunrah (Azaria, brilliantly channeling Boris Karloff), is determined to find the misplaced Tablet and use it to "unlock the gates of the Underworld." To assist him in this nefarious mission, he has recruited a wildly unlikely crew of historical henchmen: Ivan the Terrible (reliably deadpan Christopher Guest), Napoleon (Alain Chabat, approximating Peter Sellers) and Al Capone (Jon Bernthal, hulking through the film in glorious black-and-white). Upon arriving, Larry faces off against these characters with his own team, which includes Octavius and Jedediah, a living bust of Teddy Roosevelt (Robin Williams), life-size Indian-fighter George Armstrong Custer (Bill Hader) and a capuchin monkey who may also be a holdover from the first film, although with simian performers it's hard to tell. Also weighing in on the action are Attila the Hun, Darth Vader, Oscar the Grouch, a pack of bobblehead Albert Einstein dolls and the very large president seated in the Lincoln Memorial. (I'm leaving out an Indian scout, a puppyish T. Rex, a giant kissing octopus and a dancing Jeff Koons sculpture, among several other things.)

Larry's key ally, though, is pioneer aviator Amelia Earhart, played by Adams with perky bobbed hair and a sassy attitude straight out of '30s comedy classics. ("You haven't been able to take your cheaters off my chassis since we met," she tells Larry, who does indeed think she's pretty swell.) Adams brings an irresistible fizz to every scene she's in, and the sequence in which she and Larry pilot a vintage plane up into the starry night sky over Washington is CGI at its most expansively romantic.

The picture is so crammed with characters that a number of them get lost amid the hubbub. Ricky Gervais, returning as Larry's ex-boss at the New York museum, is little more than a plot blip; Wilson and Coogan don't have a whole lot to do, either; and Christopher Guest, starved of good lines, is uncharacteristically un-hilarious. But the script, once again written by Robert Ben Garant and Thomas Lennon, is so sharp it hardly matters. It's very funny when Larry, temporarily trapped inside a famous black-and-white photograph from World War II, whips out his cell phone and says, "Wow, four bars in 1945!" But when Amelia helps extract him from the picture and then tops him with, "If it weren't for me, you'd still be locked in that monochromatic mayhem," it's screwball heaven.

Don't miss Kurt Loder's reviews of "Terminator Salvation" and "The Girlfriend Experience," also opening this week.

Will the vampires grab more trophies than the slumdog? What was the year's ultimate onscreen WTF moment? It's up to you to decide the winners of the 2009 MTV Movie Awards. Vote now, and tune in on May 31 at 9 p.m. ET, when the big show airs live from the Gibson Amphitheatre in Universal City, California.

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