Hercules finds his family and other birthday party guests poisoned with a fatal drug that also induces violent phantasms, making them turn on each-other. To save them, Hercules's only hope is to help Callisto, Xena's evil arch-enemy, in exchange for the antidote, collect a panacea, apples from the tree of life, which grows in the hellish underworld Tartarus. Only there he discovers, once trapped, it was all another lethal ploy from Hera.
—KGF Vissers