It's basically about two children who take a vacation at their uncle's house. Their uncle grudgingly agrees, however tells the kids to not interfere with his "work". The children, Kendra and Seth, figure out a puzzle which few have figured out. The uncle decides they can "see", and he gives them special milk that allows them to see mythical creatures. Unfortunately a bunch if shit goes down and crazy stuff happens when the uncle's "monster sanctuary" becomes endangered as these demons try to unlock the ancient monster prison.
And so forth :D
