Frivolity is the name of the game for Mamma Mia!, an adaptation of the hit Broadway show, featuring musical numbers consisting entirely of material from the Swedish pop band ABBA. Not being familiar with the original show, and having only the slightest passing familiarity with ABBA's songs (who hasn't yet heard the immortally infectious "Dancing Queen"?), I went into the movie with few expectations other than to just have some fun. In that regard, it was mostly successful, but along the way its strengths struggled mightily against its weaknesses.

The stage show was notable for being the concoction of three British women: Judy Craymer (producer), Catherine Johnson (writer), and Phyllida Lloyd (director) -- all three have the same credits for the film. It's therefore not surprising that their story is engagingly feminine -- its main characters are a young bride-to-be, her mother, and the mother's two friends. Much of the activities, set on a scenic Greek island, involve their messing and playing around as they sing and dance through a plot that involves the arrival of three men, secretly invited by the bride, Sophie (Amanda Seyfried), on the eve of the wedding. They've been invited because Sophie wants to know her father before she marries, and each of them is a likely candidate. The heart of the story, though, is about the mother, Donna (Meryl Streep), as the mounting events threaten to be more than she can handle.

There's something both liberating and comedically frightening about watching three elder women (Streep and her friends, Christine Baranski and Julie Walters) acting half their age, letting it all hang out while screeching with glee between musical numbers. The movie works as a celebration of the freedom of being a woman -- not so much about a woman's place or trials, more about her choices, dreams, and paths to joy. Men are playthings here -- what they do and what they're for is almost beside the point.

We don't get to see this point-of-view often, so its presence can be welcome; that said, the movie exhibits somewhat of a lack of control. Lloyd, an established theater director, helms her first film here, and there are weaknesses apparent -- framing and distancing feel haphazard, editing and photography are inconsistent, and many of the performances could use some reigning in. The movie overall conveys a feeling of reckless abandon, true to the spirit of the show but also giving an appearance of sloppiness. There are visual sequences with stronger ambition than execution (e.g. Sophie's collapse during the "Voulez-Vous" number), and the film tends to fall back on the beautiful scenery of the islands to stabilize itself.

In a musical like this, though, the keys to victory lie mostly in the music and the performances of the cast, and here it's also a mixed bag. Not that ABBA is part of that -- you should know exactly what to expect, and their songs present themselves incredibly well as exposition, as they almost all have a natural storytelling element in them. None of the songs feel forced. So then it's up to the cast. Almost rather fittingly, the bad news comes from the men's side. The three potential fathers are played by Stellan Skarsgård, Colin Firth, and Pierce Brosnan. The first two get by, but don't have a lot of singing to do; unfortunately, they gave Brosnan the bulk of the men's singing and, well, he can't hack it. He's given at least one major number, and you can see the poor guy is really trying hard, but dang. I think that's about as far into it as I'd like to go.

On to better news: Streep is great. It turns out the woman really can sing, and in her major number -- her Jennifer Hudson moment, if you will -- she appropriately home runs "The Winner Takes It All." As the main glue that holds the movie together, Streep is more than capable, and her supporting women also sing just fine. Overall, goofiness prevails -- Mamma Mia! has the feel of an unpolished local project, and in case anyone had doubts about taking any of it seriously, it closes with the cast dressed in colorful retro shiny ABBA-esque gear vamping "Dancing Queen" and "Waterloo" (apparently the encore tactic of the stage show as well). Girls just wanna have fun? Apparently so.

(Released by Universal Pictures and rated "PG-13" for some sex-related comments.)

Review also posted at www.windowtothemovies.com