"Because I Said So" inhabits a level of the underworld where the neurotic run wild, calm is a four-letter word and one character is more or less identified as "the sister who set the family record for orgasms." It actually sickened me a little. It couldn't be any worse if each DVD came laced with anthrax.
Ostensibly this is a romantic comedy - though it is the opposite of romantic and funny like a shiv to the belly - about a mother and her three daughters, the youngest of which has either rotten taste in men, or rotten luck. The mother is Diane Keaton, while the youngest daughter is Mandy Moore. It should tell you something that Moore is the best thing about the movie.
Building off her mother-as-a-dictator performance in "The Family Stone" Keaton is Daphne, professional loon. She seems to be a baker; she lives in a million-dollar townhouse, so she must traffic angel dust, too. At any rate, she's the kind of mother who, at some point, talks simply for the sensation of mouthing words, dresses like Julie Andrews met Cruella DeVille, cries in proverbial hiccups, psychosomatically loses her voice, and eventually breaks out into song with her three daughters, who occasionally perform doo-wop numbers in front of small audiences of friends, husbands, and rotten men.
Forty years ago, women like this were either put on valium, or put away.
Daphne is borderline incoherent, a manipulator, and such an unhinged, meddling jack lope that she signs her daughter up for an online dating service, then screens the potential suitors. Unbeknowst to Millie (Moore), Daphne has set her up with an architect (Tom Everett Scott) who might be the blandest creep ever committed to celluloid. There's no reason to like him, and he's not interesting enough to hate.
Vying for Millie's affections is a musician (Gabriel Macht). He's also a single father. Occasionally, he moonlights as a saint, teaching kids and idiots to play the guitar. Of course, Millie, a caterer who moonlights as a saint teaching just plain idiots how to cook, sleeps around on the musician for sake of dramatic tension.
Other than be a showcase for Keaton roaring id, it's hard to figure out what "Because I Said So" wanted to do. It apologizes for any number of Millie and Daphne's morally questionable behaviors by chalking up to them being women in love, or heat, as if this somehow makes their choices look better. Directed by Michael Lehman (a long way from "Heathers" or even "Soapdish") it revels in frank, predictable chats about sex. Eventually, the daughters conclude that mom's meddling traces back to her need to get screwed; she's two éclairs short of a dozen because she hasn't been properly stuck in thirty years.
It trades in a bunch of other irritations, too. The musician's kid seems to be autistic; he's constantly screaming or running around like he's been sprung from the bull pit in Pamplona. The song numbers are so obviously lip-synched that you're not even sure what to imagine, nor is it immediately clear what song Daphne and her daughters are even trying to sing.