Upon moving to Sentinel House, five-year-old Matty and fifteen-year-old Graham encounter ghosts from a nearby abandoned military compound, but real trouble begins when their father is arrested for posting information about a secret weapons system on the Internet.
- ISBN10 0316604658
- ISBN13 9780316604659
- Publish Date 1 September 2001
- Publish Status Out of Print
- Out of Print 1 July 2021
- Publish Country US
- Imprint Little, Brown Books for Young Readers
- Edition Us ed.
- Format Hardcover
- Pages 192
- Language English