Josh, Danny, and the mad scientist Petty Potts waltz over to the zoo and try out an awesome spray that turns them into anacondas! But when Petty wanders off, the twins soon realize that they are in danger of being put in a cage with the other anacondas. Which means, when the S.W.I.T.C.H. spray wears off and they turn back into boys, they will become a tasty snack for the snakes!