What secrets lay within the walls of the house by the lock? What secrets, if any, are held by the man who owns that mysterious house? A body is found in a backwater creek not far from the house by the lock, but what leads Noel Stanton on a quest to determine who the killer might be is more than merely the disappearance of his American friend Harvey Farnham. He has reason to believe that the wealthy and influential owner of the house, Carson Wildred, might somehow be implicated in the coincidental disappearance and murder...

The hearty, all-American Rover Boys sail by yacht to Africa in search of their kidnapped father.

Third entry in the then-popular boys' adventure series has the Rover brothers (Tom, Dick, & Sam) heading to Africa to search for their long-missing father, after a few more adventures at their upstate New York boarding school, Putnam Hall.

Despite the title, the Rover Brothers spend several chapters -- over half the book -- back East, against arch-nemeses Josiah Crabtree and the Baxter family. Formulaic fun was dated even by the 1940's when Orson Welles satirized it on the radio.