The Mystery Of Cabin Island by Franklin W. Dixon

During their winter vacation, two teen sleuths accept an invitation to stay at a wealthy collector’s secluded island cabin, where they face ominous warnings, prowlers, and sabotage on the ice. Unwilling to leave, they investigate strange clues tied to a long-missing cache of valuable medals and secrets from the cabin’s past. With help from friends, they outsmart local troublemakers, unmask the real culprits behind the harassment, and recover the hidden treasure just in time for the holidays.

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