A sequel to Brittain's "Who Knew There'd Be Ghosts?" (1985), this mystery has a certain familiar charm. Among the elements that make it so readable are its deftly defined characters, the presence of ghosts that do "not" turn out to be something other than ghosts, and a likable first-person narrator who is at once innocent in his demeanor and clever in his thinking. In order to save the historic house in which their friends the ghosts live, Tommy, Books, and Harry the Blimp must prove that a poker game played on the "Titanic" on the night it sank was rigged. Although the jacket is unlikely to draw readers, the author and title will. Full-page black-and-white illustrations appear occasionally throughout the book. An old-fashioned mystery that's sure to please.