After moving from London to an old mansion on the English coast, eleven-year-old twins Jason and Julia discover that their new home has twisting tunnels, strange artifacts from around the world, and a mysterious, locked door.

Eleven-year-old twins Jason and Julia, along with their friend Rick, match wits with Peter Dedalus, the elusive inventor who created Kilmore Cove's Mirror House, as they try to uncover the secret hidden somewhere inside before Oblivia Newton can find it.

Finley McPhee holds the scorpion key, which makes him the Defender of the Emporium in the small town of Applecross, Scotland, but now Aiby Lily and Finley's brother Doug are apparently lost in an other-worldly place called the passages, and the evil Semueld Askell has told him that if he does not surrender the key within twenty-four hours, they will be lost forever--and that is only one of his problems.