Age Group: 9 - 12 Years

Description:

In the third Hardy Boys mystery, Frank and Joe stumble onto a clever counterfeiting ring after their pal Chet Morton tries to buy a microscope and discovers that his crisp twenty-dollar bill is a fake. Soon similar phony notes are turning up all over Bayport, and the boys' detective father Fenton Hardy is wrapped up in a separate confidential case that he refuses to discuss. When anonymous threats warn the Hardys to back off — though it isn't clear which case the warnings refer to — the brothers turn their attention to the brooding old Turner mill on the outskirts of town, where strange comings and goings, hostile guards and unusually tight security all suggest something is very wrong. With the help of their new motorboat the Sleuth, Frank and Joe must uncover hidden rooms, secret tunnels and a daring criminal scheme before the gang catches up with them.