The decision to release the two-headed Diane Keaton–Mandy Moore monster Because I Said So with the scent of this year’s Sundance Film Festival still fresh in the air, which I’m sure is coincidental, provides us with an excellent opportunity to review the wayward career of the movie’s director, Michael Lehmann. Once upon a time — 1989 to be exact — Lehmann came to Park City with his first feature film, a gruesomely funny high school satire called Heathers, and, like so many neophytes before and after him, he dreamed of spinning that early indie success into a long and prosperous Hollywood career. The sheer volume of his film and television output since then would suggest that Lehmann has accomplished exactly that. But take a closer look at the work (which includes the forgettable romantic comedies The Truth About Cats & Dogs and 40 Days and 40 Nights) and he starts to seem like an object lesson in being careful what you wish for.

Like nearly all of Lehmann’s post-Heathers work, Because I Said So feels lazy and uninterested — a hack-for-hire job any number of film-school grads could have put through its uninspired paces. Set in and around Los Angeles, the film stars Keaton as Daphne Wilder, a divorced, in-demand caterer whose booming wedding business has done little to persuade her youngest daughter, Milly (Mandy Moore), to tie the knot herself. And so Daphne, closing in on 60 and worried that Milly too might end up old and alone, does what any concerned parent would: She places an Internet personal ad seeking her ideal son-in-law and then proceeds to screen potential candidates for the job. Cue musical montage of variously unattractive, socially graceless, allergy-addled and otherwise ill-suited applicants.

The cream of Daphne’s crop turns out to be dreamboat architect Jason (Tom Everett Scott), who exudes WASP-y privilege and, as everyone save for Daphne can see, might as well have “asshole” stamped on his forehead. (During one of his first dates with Milly, he berates her for damaging a supposedly priceless family heirloom, but, hey, at least he’s rich.) The fly in Daphne’s ointment, meanwhile, is a hipster musician named Johnny (Gabriel Macht), whose boho charms do little to endear him to Mom, but who we know is really the guy to root for because he’s chosen the artist’s life over the world of corporate conformity — even if it is a lifestyle made possible by the fact that Johnny still lives at home with Dad. Milly starts dating him too, and from there Lehmann and screenwriters Karen Leigh Hopkins and Jessie Nelson (the duo responsible for the equally insipid Stepmom) make some halfhearted stabs at door-slamming farce as they limp toward that inevitable “gotcha” moment at which all the characters discover what’s really going on and Daphne’s whole duplicitous house of cards comes tumbling down.

Despite the movie’s best efforts to turn him into a sort of Chet Baker caricature, Macht has a sly charm and a natural chemistry with Moore (who is sufficiently charming, but little else, in a far less rewarding role than she had in Saved! and American Dreamz). But Because I Said So is a work of comic desperation, and an especially cruel betrayal of Keaton, who looks radiant in her 60s yet keeps finding herself cast in roles that use her age as the foundation for cut-rate slapstick. First there was Nancy Meyers’ Something’s Gotta Give, in which the sight of a naked Keaton sent Jack Nicholson into hysterics. Now there is this film, in which it is Keaton who’s in panic mode, projecting her own romantic failings onto her child and, in one unfortunate recurring gag, getting her computer accidentally stuck on the same porn Web site (while her dog compulsively pleasures himself). And when Lehmann can’t humiliate Keaton any further, what does he do? Why, assemble the cast for a group song, of course. I’m not saying that Lehmann shouldn’t have traded his hand-to-mouth indie-filmmaker existence for the comforts of the studios. But let Because I Said So be a warning to all who would follow in his footsteps.

BECAUSE I SAID SO | Directed by MICHAEL LEHMANN | Written by KAREN LEIGH HOPKINS and JESSIE NELSON | Produced by NELSON and PAUL BROOKS | Released by Universal | Citywide

Advertising disclosure: We may receive compensation for some of the links in our stories. Thank you for supporting LA Weekly and our advertisers.