Living with her aunts when her parents take a year's sabbatical, the teenager finds it difficult to fit into her new surroundings, and matters are complicated when bizarre things happen around her with increasing frequency.

While exploring ancient Rome, the teenage witch falls in love with a man who wants to expose her supernatural ties.

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, Dr. Julian Martin, determined to find the colony as his claim to fame. While Sabrina finds romance with Barnaby, a "merman" from the mermaid colony, Salem the cat finds a posible romance with another witch-turned-into-a-cat, named Hilary, but finds Sabrina's problems interfering with his plans.