Some of the best romantic comedies have sprung from downright creepy premises. Think Tootsie (guy woos girl in guise of middle-aged woman) or Cyrano de Bergerac and its update Roxanne (guy woos girl in guise of hotter guy). The Switch sets some kind of record in this category: It’s about a guy who woos a girl by sneaking his sperm into her uterus. Now, that’s romantic.

Surely the only way to treat this scenario — inspired by a bone-dry New Yorker story by Jeffrey Eugenides — is as the blackest, cruelest of comedies. Sad to say, directors Josh Gordon and Will Speck (Blades of Glory) do not go that route. Having cast a fine lead actor capable of both dark and light moods (Jason Bateman), they proceed to treat the material like your standard Jennifer Aniston vehicle. The flat-footed screenplay by Allan Loeb (21) seals the deal.

How uninspired is that script? Over an opening montage of bustling urban scenes, Bateman voiceovers that everyone seems to be running somewhere. “No wonder they call it the human race,” he muses.

Things get a little more interesting when Bateman’s character, neurotic finance guy Wally Mars, meets a homeless man who hisses, “Beady-eyed little man-boy!” in his direction. Like the Head Crusher on “Kids in the Hall,” this homeless man seems to exist solely to remind urbanites they’re really just glorified cave men exulting in their cruel hierarchies. He is funny, which could be why he never reappears.

Wally’s best friend and the secret love of his life, Kassie (Aniston), also seems to think he’s a beady-eyed little man-boy, though she’d never say so. Having long ago relegated him and his collection of tics to the “friend zone,” Kassie blithely tells Wally of her plans to conceive a child with sperm from a more suitable donor — a studly married professor (Patrick Wilson). Then, to complete her tactful handling of the situation, she invites him to her “insemination party.”

Soused and miserable, Wally just happens to get access to the cup containing Wilson’s donation. You can guess what happens next ... and probably also what happens seven years later, when Wally first meets Kassie’s big-eyed, anxious, neurotic son, Sebastian (Thomas Robinson). In fact, I’m guessing you think you already know how the film ends. And you’re right.

Among other things, The Switch is a paean to genetic determinism. (Who knew you could inherit so many quirks from a parent you’ve never met?) But one of the things it is not, for the most part, is a film about real people. Kassie is a void at the center of the movie; all we know about her is that she wants to spawn and isn’t above practicing amateur eugenics.

With her wheaten tresses, weirdly inexpressive eyes and generic type-A mannerisms, Aniston seems like a better mate for “Sex and the City”’s Carrie Bradshaw than any mere man. There’s zero chemistry between her and Bateman, who comes alive mainly in his scenes with Jeff Goldblum and the precocious Robinson. Juliette Lewis, who’s turning into a brassy broad in the Stockard Channing mold, also earns a few laughs.

Bill O’Reilly has taken exception to some real-life remarks from Aniston, who dared to suggest families don’t always need a father. He’d be happy to know the film appears to endorse his position. If you want to see a timely, irreverent movie about sperm donation, I suggest The Kids Are All Right. Because, regardless of whether children need a dad, a comedy needs the funny.