Cole Hillman (Rory Calhoun) is out riding on his Arizona ranch when suddenly his horse stumbles in a rabbit hole and breaks its leg. Reluctantly he is forced to shoot the horse to put it out of its misery and walks back to his farm house, making up his mind to do something about the rabbit population explosion on his land. He contacts official Elgin Clark (DeForest Kelley) who knows scientists who can help, scientists like Roy Bennett (Stuart Whitman) and his wife Gerry (Janet Leigh) who at this moment are studying bats. Roy takes a little persuading, but agrees to assist and works out a plan to keep the rabbits' numbers down - but the plan has unforeseen and deadly consequences...
Utter the phrase "killer rabbit" to a film fan and they will probably think of the one in Monty Python and the Holy Grail, but the second one they will think of may well be this notorious and bafflingly ridiculous horror. It was produced by A.C. Lyles who was best known for his western movies which gives this effort the feel of a cowboy picture gone insane. Scripted by Don Holliday and Gene R. Kearney, it was based on the novel "The Year of the Angry Rabbit" by Russell Braddon, and fit right into the cycle of revenge of nature movies of the seventies that was ushered in by The Birds in the previous decade.
The vengeful animals this time are bunnies, and what happens is that Roy and Gerry work out that injecting them with hormones will make them less likely to breed. Alas, there is a side effect in that the creatures grow, and when their daughter Amanda (Melanie Fullerton) takes one for a pet, what do you know? It gets away from her and starts doing the bunny thing with the local rabbit community. It's not long before there are strange things afoot, such as when Amanda and her friend go to visit a miner at his claim and find not only a dead body, but something large lurking in the darkness of the old mineshaft that traumatises Amanda.
The film makers go to great lengths to make this appear as serious as possible, and that is their downfall. An opening sequence features a staged news report with the newsreader telling us of the menace rabbits represent to farmers and the problems they had with the critters in Australia, but there's a big difference between normal sized rabbits destroying crops and giant sized rabbits devouring people. The difference being that while a massive insect, as in Empire of the Ants for example, can provoke chills, a cute little furry rodent looks absolutely absurd filmed in closeup and with fake blood smeared across its chops.
Although the movie is called Night of the Lepus, it actually takes place over more than one night. The first evening sees the attempt to blow up the huge rabbit warrens fail when many of them burrow to freedom, and a whole bunch of the growling, roaring rabbits go on the rampage. Quite why they should be eating humans isn't explained, but they do, and the threat finally has to be made public. Meanwhile, we get to see gory encounters with bunnies galloping down miniature landscapes towards panicking actors, and even more hilariously, men in bunny suits launching themselves at the cast. If there was a hint of intentional humour about any of this it might be easier to take, but it expects the viewer to be as appalled as the characters, which they may be, but not for the same reasons. Music by Jimmie Haskell.