S1·E42 Dracula's Potion

The Defenders set out for Transylvania to investigate the disappearance of John Harker, a young archeologist doing re-search in the area. Upon arrival, they are invited to the castle of Vlad, a mysterious local who serves them dinner at midnight. When Vlad proposes a toast, everyone joins in, except the Phantom, who doesn't trust the shifty host. The next day all the Defenders, with the exception of the Phantom, turn into animals reflecting their personality characteristics- Vlad had spiked their dinner beverages with a magic potion. Dynak X launches an antidote to our heroes via a guided rocket. Kshin, now enjoying himself as a spider monkey, retrieves the antidote from the garden and, with the Phantom, frees the Defenders/animals from their cages and administers the antidote. Restored, the Defenders turn bright lights on Vlad, trans-forming him into John Harker! The young man had been possessed by the older vampire, Vlad.