Vacations are supposed to be fun. Many people travel to far away places they've never been before, some visit relatives, while others go to the nearest lake, pitch a tent and enjoy the beauty of nature. That's exactly what Stumpy, Mary Lou, Henry and Bill did - but on the first night Mary-Lou wakes Henry as she's frightened. For a little while now, she's been able to hear a strange sound. Henry's not much comfort, and is just as frightened, so they wake Bill...