Three months ago, when Ernie P. Barber came to Treverton from Los Angeles, he'd been like a missile aimed at trouble. And Ernie had chosen Jeff to be his best friend, whether he liked it or not. “You're my buddy, old buddy,” Ernie would always say, “. . . and I'm going to cut you in on my T.S.P.” But when Ernie dies as a result of a freak accident, Jeff's troubles are only beginning. The ghost of Ernie P. starts to haunt Jeff. At first, Jeff thinks he's going crazy. But when the letters T.S.P. (Ernie's code for Top Secret Plan) and some newspaper clippings keep mysteriously appearing, Jeff is convinced that Ernie's ghost wants him to carry out the T.S.P. alone-whatever it might be. Not until Jeff faces terrible danger and stands up to the ghost of Ernie P. does the mystery of the T.S.P. unravel.