Sabrina travels to Australia's Great Barrier Reef with her best friend Gwen, a fellow witch from England, for a week-long vacation where they try to help protect a hidden mermaid colony whose habitat is threatened by ocean pollution, and by a local marine biologist determined to find the colony as his claim to fame. While Sabrina finds romance with a "merman" from the mermaid colony, Salem the cat finds a possible romance with another witch-turned-into-a-cat, named Hilary, but finds Sabrina's problems interfering with his plans.
Melissa Joan Hart
as Sabrina Spellman
Tara Strong
as Gwen
Scott Michaelson
as Barnaby
Lindsay Sloane
as Fin
Nick Bakay
as Salem Saberhagen (voice)
Peter O'Brien
as Dr. Julian Martin
Rebecca Gibney
as Hilary Hexton, the Cat & Woman
Conrad Coleby
as Jerome Hestor
Steve Harman
as Dr. Martin's Assistant
Ben Lawson
as Waiter
Victor Parascos
as Helicopter Pilot
Enrico Mammarella
as Resort Manager
