Hidden in Plain Sight: The Otherside and Beyond book 4 (Volume 4)

In the land of Faerie all is not as it seems. Simon has become obsessed by the carved doors into the King of Faerie's Great Hall and now he has disappeared. His wife, Marianne can no longer sense him. Meanwhile, Eleanor Harrington returns home to discover an unwelcome and dangerous visitor in her garden. The half man half tiger creature has been waiting for her. But surely... he should be imprisoned with the demon known as the Cambion in a realm where escape was impossible... shouldn't he? And why are John Dee and his familiar Poison Ivy still hanging around? what do they hope to gain?