The Boggart and the MonsterHardcover, 1 April 1997

It's been two years since Emily and Jessup Volnik visited ancient Castle Keep in Scotland, and made the acquaintance of the Boggart, a mischievous shape-shifting spirit who lived in the castle for centuries. Now they've returned for another Scottish adventure, joining their old friends Tommy and Mr. Maconochie, the new owner of Castle Keep, on a trip to Loch Ness where a new expedition is determined to find the fabled monster.

Of course, the fun-loving Boggart comes along for the ride, and wherever the Boggart goes, things are bound to get lively. But this time, the Boggart has a serious mission. His cousin Nessie is trapped in the monster shape he assumed long ago, and it's up to the Boggart to keep Nessie from being discovered by the expeditions high-tech equipment. Is modern science any match for the Boggart's ancient magic?