Something strange is happening in the Brewer household. Margaret and Casey's father, a botanist who recently lost his university job, has turned the basement into a secret laboratory—and the kids are forbidden from entering. But Dr. Brewer is acting weirder every day: he's growing a beard he never had, eating plant food, and there seems to be something growing on his head. When their mother leaves town, Margaret and Casey can no longer resist investigating. What they discover in the basement is horrifying—their father's experiments have created a monstrous plant duplicate of him. Now the twins must figure out which father is real before it's too late.
