Andrew, Marie, their mom, Duffy, and Aunt Elise are on their way to a friend's cabin.
They arrive at the cabin and realize that is actually a big house that needs cleaned out. They clean out some rooms for themselves.
Next, Andrew found a message on the wall, "BEWARE THE SENTINEL." He told everyone, but they said it was just a joke.
BEWARE THE SENTINEL
They went for another walk in the woods. They took off their jackets, but Duffy left his in the woods.
They were going to hide in the barn from the monster, but the doors had a padlock on them.
Their mom and Aunt Elise went to buy some supplies from a store. They left Andrew, Marie, and Duffy at the house. They were playing Monopoly when they heard a scratching at the door. Duffy looked and saw it was something big.
They went back into the house and the creature followed them. It came into the room, said "You forgot your jacket, stupid," and threw the jacket at Duffy.