Better monster babies out there

The horror-comedy “Cynthia” puts a cartoonish spin on the “monster baby” subgenre, kind of like the 1974 classic “It’s Alive,” but with slapstick instead of squirmy suspense and social commentary. Screenwriter Robert Rhine and co-directors Devon Downs and Kenny Gage have made something polished, colorful and energetic but, ultimately, pretty disposable.

Scout Taylor-Compton stars as Robin, a well-to-do suburbanite whose marriage to self-absorbed Michael (Kyle Jones) has been on the rocks as they’ve struggled to conceive a child. The relationship doesn’t improve when Robin finally gets pregnant, only to find that her baby has a “twin” — a mysterious lump that the doctors assume is a benign cyst but is actually a snarling, homicidal creature.

“Cynthia” has some entertainment value whenever the beast attacks. The filmmakers construct those scenes well, maximizing the grotesquerie.

But much of the rest of the “comedy” in “Cynthia” is awfully bland, riffing on the shallow materialism of the uppermiddle-class. The picture does build to a properly crazed crescendo, showcasing an impressively disgusting monster. Overall, though, there’s maybe 20 minutes of worthwhile material in “Cynthia” — and even that offers little that “It’s Alive” and “Basket Case” didn’t do better. “Cynthia.” Not rated. Running time: 1 hour, 29 minutes. Playing: Laemmle Glendale.