A CRAFTY editor could take The Back-up Plan and turn it into a horror story: too-trusting J-Lo is lured to a rural goat farm and forced to foal the anti-Christ by cultists. A natural childbirth scene has a tattooed weirdette ululating like Yma Sumac, so there would be room for the appropriately hellish wails on the soundtrack. Until that's done, you must watch what's onscreen—or listlessly text messages to friends as the Cosmos slowly wear off. The Back-up Plan is padded with dog-reaction shots; Nutsy the Crippled Boston Terrier gets more arf than larf. He has the final bark: "So long, suckers!" is what it sounded like to me.

The blinking dog adds to the running time, which also lards on the distinctions of J-Lo: "You're this incredibly accomplished person—sweet and sassy" and so forth.

Lopez plays Zoe, a Manhattan boutique pet-store owner who has given up hope on Mr. Right and has decided to go for a turkey-baster babe. Shortly after impregnation, she fights over a cab with Stan (Alex O'Loughlin, combining the least-interesting elements of Dermot Mulroney and Keanu Reeves). This is what passes for a meet-cute. It gets done twice, in case we missed it the first time. She falls in love, but has trouble telling him that she's got a stranger's seed in her womb.

Your typical romcom hunk has been greenwashed here; Stan runs a goat-cheese stall at the Tribeca farmers market, and he has a herd of goats upstate. He apparently milks them through osmosis, because the farm goes on the backburner. Making Stan a cheesemonger gives critics a free one. But artisan cheese makers work hard for a living, and this movie isn't even as earthy as Kraft. Ultralong snits follow every fake-ass argument.

Speaking of ass, Lopez memorializes her salient feature: "I miss my old butt." Let's say that Lopez's appeal was due to face matching ass, a pertness and insouciance at both ends. Whatever she had has fled. Lopez tries to recall it like a politician might, through an assumption of earthiness: eating wieners from Gray's Papaya or chowing down on pizza.

The movie is a bizarre mix of the clinical—dog spew, doo-doo, vadge blood on a doctor's glove—and the bland, expensive and idealized: Zoe goes into labor with perfect makeup on and an orchid behind her ear. No relief by Michaela Watkins as Zoe's best pal, a bitter housewife; her four kids seem to be raising themselves, like the pets and the goats.

When a star vehicle goes this wrong and is this out of it, one has to agree with what Stan says to Zoe after one of their pointless fights: "When you do the autopsy on this, you'll find there's no one to blame but yourself."

THE BACK-UP PLAN (PG-13; 106 min.), directed by Alan Poul, written by Kate Angelo, photographed by Xavier Pérez Grobet and starring Jennifer Lopez, plays countywide.

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