Stay Out of the Basement

Stay Out of the Basement is the second book in R.L. Stine's Goosebumps series.

Plot
Dr. Brewer has been acting strangely, spending nearly all his time in the basement of his house, working on his plant experiments. He had warned his children, Margaret and Casey, to stay out, but they sneak in and catch a glimpse of gigantic plants. They begin to worry even more when Margaret finds that her father has been eating plant food, sleeping on a layer of dirt, and bleeding green blood. After his baseball cap is knocked off to reveal leaves growing from his head, Dr. Brewer explains that he is working with genetic engineering, in order to create a plant/animal hybrid.

Eventually Margaret and Casey return to the basement and find another Dr. Brewer bound and gagged in the closet. The siblings and their mother learn that the "Dr. Brewer" they've been living with for some time is actually a nearly perfect plant/human clone of the real Dr. Brewer. The clone, along with most of the plants, are destroyed by the real Dr. Brewer with an axe, while a few of the normal plants are moved into the garden.

In the final twist, which is a staple of the Goosebumps series, one of these plants speaks to Margaret, claiming that it is the real Dr. Brewer, but this development is left hanging.

Television adaptation
Stay Out of the Basement was adapted as a two-part episode in the Goosebumps television series, which has since been released on VHS and DVD. However, in the television episode, the Diane Manning character was not present. Also, the ending is changed; instead of one flower telling Margaret that she's her real father, it's an entire garden of flowers who keep repeating "I'm your father!"