Stay Out of The Basement (Goosebumps: The Graphic Novel #3)

Do not enter ... or else!
The basement is strictly off limits to Margaret and Casey Brewer. Their scientist dad is running a secret experiment with plants and doesn't want them upsetting the delicate ecosystem he's created.
But Margaret and Casey decide a quick peek won't hurt anyone. Their dad has been behaving very strangely and they have to know what's going on down there. The truth they find is way stranger than fiction-these plants just might have minds of their own!