Sometime during exam period three years ago a fanfare interrupted an otherwise peaceful dinner in the Freshman Union. Weary Freshmen looked up to see a large white sheet emblazoned with a pink "A+" unfurled from the balcony. A figure well over six feet tall in a white lab coat appeared, shed the coat, and dropped down to the floor of the Union dressed in a black wet suit with another pink "A+" painted on the chest. The man in the wet suit then ran throughout the Union distributing previously graded blue books. The grades were, of course, all A plusses. No one's seen "Captain A+" since.

Like his roommates in Old Quincy, Chris Petersen--the mysterious Captain--hasn't been in Cambridge in two years. While most of the rest of the class of '77 lived the spoiled student life, Petersen, Dan Davis, Chris Kimball, and Tom Stromberg, willingly lived Spartan existences scattered throughout the world as missionaries for the Church of Jesus Christ of Latter Day Saints.

For two full years, these four Mormons followed a strict regimen: Up at five or six in the morning; after washing, an hour and a half of Gospel study unti breakfast at 7:30 or 8:00. Followed (since none of the four speaking countries) by two to three hours of language lessons. The missionaries, armed with seven basic memorized lessons about their religion, would then go out into the country to spread their Gospel, sometimes staying out until after midnight.

They would do this six days a week, the seventh day being their own--but only until five or six o'clock, when they would teach class or attend meetings.

During their free day they would write letters, wash clothes, buy food at the store, and go sight seeing. Petersen once sent a letter from Costa Rica filled with termite droppings to some stoned friends who had lived in his old Wigglesworth entry. He enclosed a message saying "Smoke this, it'll really get you off," and signed it with a phony name. But Stromberg tried to keep his letter-writing and errands to a minimum so that he would have more time to see Japan, the country he was assigned to.

The other six days they would proselytize with tactics they now encounter every day in Harvard Square: knocking on doors; buttonholing people on the street; holding public meetings; and even walking right into businesses to try to convince employees of their version of truth.

Davis, who came to Harvard from Downing, Idaho, and spent his mission in Paraguay and Uruguay, even tried hitchhiking. He found it easy to contact potential converts that way because drivers were usually interested in why an American boy in suit and tie was hitchhiking on South American roads. That gave him a natural chance to explain the purpose of his mission, and the Mormon doctrine.

Davis wrangled a one-hour private audience with the head of one of Paraguay's largest corporations through fellow missionaries who had hitched a ride with him. "He told his secretary, 'No calls and no visitors for an hour,' and we sat down in his office and drank Cokes," Davis relates. 'He turned out to be Jewish, and he invited us to his home for the Sabbath, provided we didn't talk about our religion."

Stromberg, a native of Salt Lake City, used Japanese respect for Americans to his advantage. "The Japanese treated me as if I was 30 years old," he says. "I could walk into a bank and ask to talk to somebody, and they'd usher me right into the branch manager's office."

Stromberg also used his Harvard ties. "The Japanese respect Harvard because of Edwin O. Reischauer. They'd ask me if I'd ever met him, ever talked to him, and I'd say yes, I have met him, and then they'd be in awe."

The missionaries used ploys similar to highschool bake sales to attract audiences. Petersen -- whose mission took him to Panama, Costa Rica, Nicaragua, and the Honduras--organized Bible study groups, cleanup campaigns, and bike-fixing clinics.

But the missionaries learned that, as Americans, they were not always welcome. Davis discovered the hard way that some Uruguayans still harbor grudges about American political intervention. During Davis's mission one of his compatriots was shot while going door-to-door in Montevideo. Davis himself says that he had a knife pulled on him more than once, but was never physically hurt.

Petersen says that several times he found himself looking down a gun barrel, but was diplomatic enough to escape unharmed. Even though some Central Americans may not have welcomed him, or Americans in general, they loved one in particular: Both Petersen and Davis constantly received requests for pictures of John F. Kennedy.

"I would walk into a home and see tapestries of the saints and the Kennedys side by side on the walls," Petersen says.

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