It happened during the Christmas holidays of 1928. The twenties were still roaring, Calvin Coolidge was still in the White House - though the Hoovers were busy packing their stuff and preparing to move in the following March, and it would be a little less than a year before the Great Depression would wreck the capitalist dream.
It was cold that winter in New England, bitter cold. It was so cold that many of the bays and inlets along the Atlantic coast were iced over, a situation that provided much pleasure to the young people who populated the small coastal villages. Many spent their school holidays on the ice either skating or sailing in homemade "ice boats," small crafts powered by sails.
It was one of these homemade ice boats that carried four high school lads and their camping gear out across the frozen bay toward an abandoned island. Though the boys had no way of knowing at the time, their winter camping trip was destined to be a very dangerous excursion- one where they would be pitted against ice and snow, hurricane gale winds, wild animals, and a determined criminal working in tandem with two local hoodlums. Fortunately, they had taken the precaution of bringing along their rifles.
What the young men discovered on Cabin Island was so strange and bewildering that it took more than a year for an aspiring writer to record the incident in book form, and even then, a year after the fact, the writer thought it best to use a pseudonym.
The boys had planned to do their camping in an abandoned cabin that was owned by an older friend, a man who had recently given two of them a hundred dollars each as payment for some personal services. They unpacked and got comfortable in the old cabin, building a fire in the massive fireplace and fixing lunch.
After lunch the naive foursome decided to go out onto the bay and play around in their ice boat, a craft that two of them had built in a joint effort. While they were out skimming across the ice, one of the lads thought that he saw a stranger walking around on Cabin Island. That was worrisome because they were the only ones with permission to be on the island during the winter holidays. When they finally got back to shore and climbed the steep hill to the cabin, they learned that there had been an intruder on the island, and he had stolen all of their supplies.
The following day two of the boys went to a rustic grocery store on a neighboring island where an aging shopkeeper told them a strange tale of a crime that had taken place in the area many years before. The victim of that crime was the old man who had befriended the lads and loaned them the use of his cabin.
After returning to the cabin, the two boys, who happened to be brothers, joined their friends in a search of the surrounding area in hopes that they could find their missing supplies hidden someplace in the snow. They ultimately were successful in their search because the load had been too heavy and cumbersome for the intruder to carry down the hill and to his ice craft. But while searching for the food, they also came across something else of interest: a notebook containing a mysterious cipher:
XZYRM. RHOZMW. XSRNMVB. OVUG. UILMG. MRMV. UVVG. SRTS.
With that important clue the chase was on. Before the mystery was solved there would be a catastrophic ice-boat wreck, a cross-country race to track down a couple of marauding nocturnal thieves, and the cabin would be almost completely destroyed by a winter hurricane. Biff the pugilist, Chet the over-eater, and Fenton Hardy's boys, Frank and Joe, were on the case!