Something is amiss in Bayport, the Hardy Boys' home town. First, there is trouble in Shantytown, then a strange black craft tries to ram Joe and Frank's boat, the Sleuth. That night the local bank is robbed. And later that same night the young...
Counterfeit money is in circulation, and the limit is reached when Mrs. Hardy takes some from a stranger. Then the Hardy boys and their high school chums are warned to stay away from the old mill. Their curiosity plunges them into peril of the...