 Pammie Goodwin s pet rabbit, Cleo, accidentally swallows one of Martin s vitamins, which causes Chloe to grow into a monster rabbit. Martin has to figure out how to restore Cleo. In the meantime, it s a tough job to hide a 6-foot tall rabbit, one with a 6-foot tall rabbit appetite, from the searching Pammie, Mrs. Brown and Det. Brennan. Before Martin can give Cleo the antidote he concocts, Cleo ingratiates her way into Mrs. Brown s masquerade party, and has such a good time, she doesn t want to take the antidote to become a regular rabbit again. Martin secretly slips Cleo the antidote just in time.