Author is John Hudson Tiner. Description: When Davy Wilson and his friend Tommy T rebuild an old VW bus, they are catapulted into the dangerous waters of a twenty-five-year-old mystery. At stake is the Wilson family's reputation, as well as a priceless book autographed by Abraham Lincoln. In the tradition of the Hardy Boys, Davy and Tommy T risk their lives in their dogged pursuit of the mysterious green-truck man, who holds the key to the solution. In the course of their adventure, Davy comes to realize that his "book learning" is as valuable to the success of their quest as is Tommy T's practical experience. It is only when the two boys work together, each contributing his own particular ability, that they can solve the mystery of the missing book.