Strangers in the Woods was the fourth story in the book, Tales to Give You Goosebumps.
It is about a girl named Lucy. While her parents are staying in Asia, Lucy is staying with her great-aunt Abigail. Lucy soon discovers that some of her great-aunt's specialties, are slightly different. Along with her, usually slow, calm driving. Her dog has also been acting weirder than usual. In fact, he's usually the PERFECT dog! Lucy then takes her dog, Muttster for a walk. Except, Great-Aunt Abigail warns Lucy to stay out of the woods, when last year (Lucy did visit last year) Great-Aunt Abigail had NO problem of Lucy going into the forest.
Lucy then starts seeing bright lights in the sky. Lucy soon expects that the lights are signs of aliens. Lucy also starts to expect that the reason her dog is barking so much is because of Muttster's sixth sense, which makes Lucy believe that Great-Aunt Abigail has been possessed by an alien. To prove that she is right, Lucy goes into the forest. She then finds out that the reason for the lights is because there is a movie going on in the forest (Which is why Great-Aunt Abigail said to stay out of the woods). Great-Aunt Abigail then explains that she has been acting so weird, because she lost her glasses. Right before Lucy goes to bed, she finds her great-aunt's glasses. She then goes to return them, only to find that her Great-Aunt Abigail is an alien.