Whilst hunting in the mountains, the boys stumble across an abandoned baby. Jason refuses to leave the child to die and insists he return home with them to Atlantis. But this charitable act has far-reaching implications, and the gang soon find themselves embroiled in a complicated web of secrets and lies. With their own lives now on the line as well as the child's, it seems they may well pay the ultimate price for interfering with fate.

Desperate to win over Medusa's heart, Hercules pays a visit to a powerful witch, Circe. But events take a malevolent turn when Hercules realises he has unleashed a potent but toxic enchantment that threatens to turn his burgeoning hope into unbearable grief. With a bitter chain of events rapidly unfolding, it is up to Jason to undo history before it is too late. As he re-traces Hercules's steps into the mountains he is unaware that a deadly trap has been set for him; one with far-reaching consequences beyond the fate of just his friends.