When Marco gets hit by a bat while playing baseball, he begins to hear a voice that identifies itself as Keith, a resident of Marco's basement, who turns out to be a slimy monster. Original.
- Author(s): R. L. Stine
- Publisher: Scholastic Incorporated
- Language: en
- Pages: 111
- Binding: Paperback
- Edition: 1st THUS
- Published: 1997
- Dimensions: Height: 0.9842519675 Inches, Length: 8.661417314 Inches, Weight: 0.25 Pounds, Width: 5.905511805 Inches
- Estimated Delivery: Dec 28, 2025
