_by Capwell Wyckoff_
When Don and Jim Mercer and their buddy Terry Mackson set out in their
sloop, _Lassie_, for a visit to Mystery Island, they were in search of
adventure and fun. But they quickly found they were getting more than
they bargained for—real danger, a skirmish with marine bandits, and a
fight for their lives. This is a thrilling adventure story of three
modern boys—with action and excitement on every page.