"This was not child's play," recalled the man on the secret mission. "Flying 600 miles away from the nearest humankind over the polar ice cap, where survival is counted in the hours and minutes rather than the days, you are almost constantly aware of your frailty and of your dependence on the will of God. . ."

The purpose of the mission: To hide a case of Canadian Club Whiskey, retail price, about $125.

For 12 years, the people who sell Canadian Club have been sending men around the world to remote places, hiding their cases of whiskey, running the clues in slick magazines, and challenging the thirsty or adventurous to find them.

It all began on July 21, 1967, when a team of ad agency men left New York City on assignment for their client, Hiram Walker Inc. Their destination: Tanzania, East Africa. With them they had a case of C.C. whiskey.

A few days later the team flew over the southern slope of Mount Kilimanjaro and dropped the case of spirits by parachute.

Having successfully bombed Hemingway's favorite mountain, the people at Hiram Walker decided to pursue the campaign and in January 1968, a second case was hidden under Angel Falls in Venezuela. A third case was hidden on the Great Barrier Reef off Australia later that year.

An agency spokesman said, "Never in our wildest imagination had we expected anyone to actually search for one of our cases, much less find one."

But the case in Venezuela was found -- only a month after it was hidden -- by a pair of newlyweds, David Mattoon and his wife, Diana, who were on their honeymoon -- which Diana thought was going to be in Acapulco.

When in the air David made his first husbandly decision and said, "We're not going to Acapulco. I've decided we should spend our honeymoon in the jungles of Venezuela.We're going to look for a case of whiskey."

Having found a guide called "Jungle Rudy," who happened to be the same guide who helped the advertising team bury the treasure, they were drenched in the monsoon rains and stung by mosquitoes but found what they were looking for.

After that, the ad agency men really got serious. They hid cases in the Yukon Territory, in Loch Ness, on Robinson Crusoe Island off the coast of Chile, on the island of St. Helena and 110 feet from where Stanley met Livingston in Ujiji, Tanzania.

A local resident of St. Helena stumbled onto that case a few months after it was hidden in 1971, but the others have yet to be found. "The cases on Robinson Crusoe Island and in Loch Ness will never be found," predicts one ad man.

There's a fifth case missing, too, from the 17 that have been hidden. But anyone tempted to search for it might find it easier just to run down to the local package store. This missing case is tucked away at the North Pole.

For five years, until 1976, no other case was found and none was hidden.

Then the advertising campaign was reactivated and put in the hands of writer Tom Fenton and artist Carl Christie. They decided to hide more cases in the United States: Death Valley, Calif.; an area known as Bigfoot's Feeding Ground in the Pacific Northwest; among the Thousand Islands in upstate New York; near Bonnie and Clyde's last hideout in Louisiana; in a New York City skyscraper penthouse; in the Superstition Mountains near Apache Junction, Ariz., and in Chicago. They also hid goods at the North Pole and off Devil's Backbone Reef in the Bahamas.

A Dutch journalist, Peter Juul, aiding in the search for two missing children, found the C.C. on Mount Kilimanjaro in December, 1977, 10 years after its burial.

And a couple of prawn fishermen, sailing out of Cookstown on Australia's northern coast, came across the case on the Barrier Reef this May, 11 years after it had been hidden.

But the cases hidden in recent years have been found fairly quickly, usually in a couple of months.

"Out of the last nine cases we've hidden, eight have been found," says Fenton. "But no one has been able to find the one at the North Pole.

"Outsmarting the locals is a very big problem," he adds. "They know the cache areas better than we do."

One local, Tom Dalton, a 35 year old Portland, Ore. repair shop owner, said, "I saw the ad in Playboy and knew Bigfoot's Feeding Ground. Knew it since 1952. Went up one Friday with a friend, found the location and banged around the ground with the backs of shovels until we got the hollow sound. We dug in, and there it was."

A Vietnam veteran, Dalton piloted a helicopter for three years and even worked for a while on the Great Barrier Reef.

"I have a pilot's license and fly a lot. I used to fly up to Bigfoot every weekend. There are 66 old mines up there and my hobby is looking up old mines.

"I've been lucky in finding things. One time I was looking for squirrels and found a bag of several hundred silver dollars.

"Another time while playing in the sand on the Barrier Reef I found a woman's diamond ring."

Dalton discovered the Canadian Club in April, 1977. "I gave one bottle to Harry R. Truman, an 84 year old manager of the Spirit Lake Lodge, and another to a lawyer friend.

"But I still have 10 stashed away. I'm not much of a drinker and I've never tasted an ounce of that booze."

Unlike Dalton, 66 year old Lonnie Foster undertook a more casual search after seeing a magazine ad in April, 1978 telling about a case hidden around Bonnie and Clyde's 1934 hideout near Gibsland, La. Back in 1934, Foster was actually nearby, farming cotton and peas. The search gave him "the chance to get out and walk around a bit" following open heart surgery. So he rounded up his grandsons, Kenneth, 22 and Mark, 21, and set out.

"We were digging near Ashland in Natchitoches Parish and were playing a hunch," Foster said. "We finally discovered a little patch of ground that looked promising with nothing but a little pine tree on it. When I pulled on the tree, it uprooted right in my hand. There was the case, 12 inches beneath the ground."

The Chicago case went fast. Hidden last March, it was found two months later in the Civic Opera Building on North Wacker Drive. When the July issues of the slick magazines appeared, the clues to the Chicago find were still being printed.

"The agency printed notices of the finding in the Chicago papers," Christie explained. "For those who missed the notice and still searched for the case we had them fill out a questionnaire and they received a silver belt buckle."

Meanwhile, Fenton and Christie have just returned from the volcanoes of Hawaii and promise that clues will appear in the September issue of magazines. Then the campaign will move on to San Francisco for next May and June. The agency plans on one major city each year.