Night of the Lepus

When an experiment goes horribly awry, a herd of giant killer rabbits are sent galloping across the globe in this gross-out horror movie from 1972. The technical details of the plot, which involve a hormone designed to quash the rampant sexual proclivities of rabbits, are wisely dispensed with early on in order to allow the rampant bunnies enough screen time to rip into their human persecutors. As the giant beasts throw off the cute, loveable mantle they've worn for so long, a cast including Janet Leigh and DeForest Kelley attempts to fend them off. (official distributor synopsis)