In the early days of World War II, before the U.S. actually entered the war, Great Britain’s intelligence unit was alarmed at the large number of RAF prisoners being held as POWs all over Europe.

MI-5, British intelligence similar to today’s American CIA, concocted a plan that eventually enabled nearly 12,000 British POWs to escape and return to Allied soil.

What was the plan? Prisoners were secretly provided maps and local currency. How’d the Brits do that? An English publisher, Waddington, Ltd., learned to print maps onto silk. Paper was too perishable for a rugged escape. What about local currency?

The genius of the plan was the means of getting maps and money to the POWs. The British gave specially prepared board games -- Monopoly sets -- to the Red Cross for distribution to POWs. The Germans permitted that sort of thing in CARE packages.

Area maps were printed on silk squares which were heavily compressed and hidden inside Monopoly game board pieces. British craftsmen also fashioned playing pieces that converted into such useful items as a magnetic compass, or a two-piece metal file which screwed together.

Depending on where in Europe the Red Cross packages were delivered, local money was provided for soon-to-escape prisoners. German marks, Italian lire, or French francs were cleverly concealed within piles of Monopoly toy money. RAF air crews were briefed -- in absolute secrecy -- before each flying mission about the Monopoly game escape kits.

You may wonder how POWs could tell the difference between a "regular" Monopoly board game and one that was "rigged" for escape?

That’s the fun part. Waddington printers made a tiny red dot on each board that looked like a printer’s mistake on a single square on the Monopoly board escape kits. You may ask: "Which square was that?" The RAF fliers were told to look for the red dot on the jail square!