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.

* * *

Not only did the missionaries suffer through long hours and rough working conditions, they had no pay and poor living quarters. The Mormon Church asks that its missionaries pay for their missions themselves; if they cannot afford to live for two years in a foreign country, sponsors for the missionaries will be found to underwrite the costs. Kimball, originally from Madison, Wisc., lived in a house in South Korea for $70 a month, a fee that included room, board, and laundry. Stromberg describes the places he lived in Japan with one word: "Dumps." And though the paint may be peeling in his Quincy suite, Petersen says, "It's much nicer than any place I lived in. "One had inch-long termites that flew around the room at night."

Though Davis paid $60 a month for a single room in Paraguay, he found that even the poorer families and houses had maids. "It's less expensive to work and hire somebody to take care of the house than to stay home and get no pay," he explains.

The missionaries also had to endure a lack of privacy and no female companionship. The rules of the mission require that missionaries stay away from women at all times, and the missionaries work in pairs so that each will have a "constant companion" for safety and spiritual strength.

The constant companion is literally that. Together for several months, "it's worse than having a wife," Stromberg says. "At least with a wife you can leave home and go to work."

During his mission, Stromberg found himself paired with a potato picker from Idaho, a reformed thief from Baltimore and a Japanese missionary who introduced Stromberg to the language, customs, and life he would have to lead. But Stromberg found it very easy to get along with his companions: "You forget a lot of yourself when you're working with somebody to accomplish a common goal that exists outside of yourself.," he says. "Especially one you're totally dedicated to and believe in."

* * *

Yet, despite all the hardships the four missionaries endured, and knew they would have to endure, all left school voluntarily. Kimball applied to stay in South Korea for two more years, but was denied permission. "The church has very strict rules," he explained. Why would he have stayed? "What I did was tell people, 'Look. Here's something I've found. It's helped me, and I think it can help you.'"

Scattered about the missionaries' Quincy House suite are remnants of their last two years. Stromberg now owns an amplifier he purchased in Japan for half of what it would have cost him here. He's saving for a turntable so he'll be able to play some of the Japanese records he acquired overseas. From Petersen's bedroom wall hangs a rug he picked up in Central America, and he's looking for a place to put some Indian dress quilts. Kimball wears a watch he bought in the Orient, and he likes to lounge around the room in a pair of Korean pants. Davis wears some sandals he brought with him from South America, and when the weather's right, he'll bring out a leather coat he purchased while on his mission.

All four plan to return after graduation to the countries in which they spent their missions, and when they go back they hope to know even more about those cultures than when they left: Stromberg plans to major in East Asian Studies, Davis in Latin American History and Literature, and Petersen in Anthropology--with special attention to Central American culture. Kimball, an Applied Mathematics concentrator, plans to use his studies to examine the Korean economy.

The missionaries have returned to a changed country. South Koreans, Kimball says, told him they were worried that Jimmy Carter would become president. All Kimball could tell them was "Who's Carter?" Stromberg caught a glimpse of a Newseek cover of Carter just before he left Japan, and wondered what "that farmer who was governor of Georgia" was doing there.

They've returned to a changed university. "The place is more all-American," Petersen says. "There are fewer people here who are brilliant and frustrated. More people seem to know what they've doing. And I see more pullovers and topsiders."

"I'd heard that Harvard was a radical place," Davis adds. "When I got here I couldn't understand why it had that reputation. But compared to today, yes, it was very radical."

The changes on campus bother Kimball. The Harvard he knew two years ago, he says, was a more cosmopolitan place. "The people I knew on the wrestling team freshman year were different, came from entirely different backgrounds, but now they all fit into the Harvard mold. I'm afraid that's what happens from being here."

But Stromberg was pleasantly surprised to find that many of his original classmates had matured, even though, he laughs, some didn't notice that he had left. "People here now seem more interested in me as a person; they seem more willing to extend friendships," he says.

And the reaction from those who noticed he had left has been positive. "Nobody's said, 'Were you crazy to do that?' They're interested in knowing why we went and the experiences we've had."

Even so, the four returned missionaries requested that they be roomed together. "We thought it would be easier on Quincy House," Davis jokes.

Stromberg isn't so charitable. "I don't think I could live with any other sophomores. I'm used to dealing with pretty unselfish people. Somebody that's caught up in his own classes or grades...I'd rather not live with something like that. Looking back on freshman year I can see now that there were more important things than grades, and I know I'll be less worried about them this year. And less serious about school in general."

Davis agrees. "I think we've all realized that Harvard is just one corner, and a small corner, of the world," he says.

The roommates say they've readjusted now and are settling into the looser student routine that they left two years ago, but with minor differences. Stromberg, for instance, sits at his desk for 15 or 20 minutes a day, and writes down the qualities he'd like to see in himself, and the flaws he'd like to eliminate habit he picked up on his mission, and he saves all the little pieces of paper he's scribbled on to see how far he's come.

Kimball, a varsity wrestler as a freshman, plans to try that sport once again. Davis will see if he can sing in the Glee Club. Stromberg is considering debate, but admits that his interest is not what it was three years ago. Petersen hasn't yet decided whether or not he'll play basketball as he did his freshman year. And as to whether or not Quincy House will see "Captain A+" this year, well, Petersen's not saying.