With his big mustache and baggy skin, DeForrest Kelley looks like an adult film star whose face is melting.

Remember that scene in Monty Python and the Holy Grail when the knights come across the Rabbit of Caerbannog?

Tim the Magician: “There he is!”

King Arthur: “What, behind the rabbit?”

Tim: “It is the rabbit!”

Arthur, unfazed, sends several knights to “Chop his head off.” But the rabbit really is a murderous monster who turns the knights into a snack, freaks Arthur out and makes Sir Robin soil himself with fright. A hilarious scene all predicated on the goofy idea of a bloodthirsty bunny rabbit.

Now imagine for a moment that another director had that same rabbit vision, only his vision was serious. That director, my friends, was William F. Claxton, and his vision of a rabbit-spawned apocalypse was “Night of the Lepus.” “Lepus,” if you didn’t know, if the scientific name for rabbits, and as far as I’m concerned, “Night of the Lepus” is the scientific term for complete idiocy.

The year is 1972, and Arizona has a problem. A rancher named Cole (Rory Calhoun) lives there, and he’s arrogant, self-righteous and irritating. Yet he and his neighbors say there’s a bigger problem, that the town’s rabbits are eating all the crops. (What crops? We don’t know- they’re never shown.) Cole whines about this to his friend, Elgin Clark (DeForest Kelley of “Star Trek”), a college administrator who by definition has no idea how to solve a problem. But Elgin knows “a young couple” who might help: Dr. Roy Bennett (Stuart Whitman, still years away from “Knots Landing,” and from “Demonoid: Messenger of Death,” for that matter.), and his wife Gerry (Janet Leigh). Now these two are a “young couple” if you’re Methuselah, maybe, but they’re doing some research on bats near the college, which is proof enough for Elgin that they’re up to the task.

In his best Peter Lawford drunken slur, Roy explains his plan: he’ll give the boy rabbits female hormones and the girl rabbits male hormones, and they’ll all then suffer from gender identity crisis. While this plan won’t solve anything, it shows early on that Roy has no idea what he’s doing, and so nobody’s surprised when one of the hormone-charged bunnies escapes, grows to gigantic size and eats people.

Or so we’re told, anyway. See, fuzzy little bunnies are not scary at all, and this is why this “horror” movie is so pitiful. Director Claxton is asking the audience to essentially take it on faith that these rabbits, who are only shown hopping, frolicking and sniffing things, are really a threat to the town. It also doesn’t help that when a rabbit is actually attacking someone, the “rabbit” is very clearly a guy in a bunny suit. He punches one guy and then does a sort of karate pose. And to make things absolutely unbearable, Claxton shows us every second of every rabbit “attack.” Sorry, but if it wasn’t scary the first time, the next fourteen aren’t going to fare much better.

Since the rabbits (and the costumed people) don’t convey their inherent scariness well, it’s left to the humans to get across that these normally mild-mannered mammals are more Bugs Moran than Bugs Bunny. Kelley is no help there, and with his big mustache and baggy skin, he looks like an adult film star whose face is melting. Calhoun is too manly to be scared, and Whitman is too drunk. Even Janet Leigh, who personified terror in “Psycho,” spends more time babysitting her character’s daughter than screaming, crying or even fighting back.

So if the rabbits aren’t scary and the humans aren’t scared, how is “Night of the Lepus” a scary movie? It’s not, of course, it’s an unintentionally laughable one. Unless you consider that this was a studio picture- an MGM one, to be exact. If that isn’t scary, I don’t know what is.