This book has some issues: Gretchen and Clark are left with their grandparents who lock them in with a monster. Basically they're bored so they go in the locked room they're told not to enter because of the danger, and discover a monster inside. They run madly around the house trying to kill it and discover that their grandparents deserted them to "get help". Luckily the monster is allergic to humans and dies, but that does nothing to stop its evil siblings in the swamp outside. ( )