Malawi, a tiny capitalist-oriented nation known for its stability in the midst of wars, chaos and socialist malaise in southern Africa, is finally beginning to pay the price for years of one-man rule.

The country is literally the creation and life work of its octogenarian president, Hastings Kamuzu Banda, an American- and British- licensed physician. Ever since he brought Malawi to independence from Britain in 1964 he has run it as his personal fiefdom with his 6 million people acceding to his unquestioned authority.

By the standards of their neighbors, however, Malawians have prospered. The country, the size of Pennsylvania, feeds itself, a rarity in Africa, and generally has been spared internal strife.

Banda is president for life, but as that life begins to ebb there are signs that age is beginning to gnaw away at his heretofore iron grip on the nation.

So, despite government denials, the fight for the succession is under way with a vengeance, highlighted by the deaths in mysterious circumstances of four senior officials six weeks ago.

The drama, which involves few verifiable facts but countless rumors, has all the qualities of a peculiarly African version of "King Lear." His Excellency the Life President Ngwazi Dr. H. Kamuzu Banda, as he is formally known, is the protagonist.

He is the ngwazi, the revered tribal leader, the champion in Malawi's Chichewa language. One of the sayings of his Malawi Congress Party, the country's only political organization, is "Kamuzu knows best."

"The Malawi style is what Kamuzu says; it's just that, and then it's finished," he told his people 19 years ago. "Whether anyone likes it or not, that is how it is going to be here. No nonsense, no nonsense. You can't have everybody deciding what to do."

Banda's official age is 77, but most longtime observers here think he is 85 or older. Even though he looks robust and healthy in his public appearances, there is growing belief that he has good and bad days and that the bad days are increasing.

A diminutive man who brandishes an ivory chieftain's stick and a fly whisk, he is an outspoken foe of communism and the only public black friend of white-ruled South Africa. An avid reader of Roman history, he has told underlings, "The reason the Russians are such barbarians is that they were never conquered by the Romans."

He also has a rigid moral code, banning shorts, trousers or skirts above the knee for women and long hair or flared trousers for men.

The rest of the dramatis personae in the palace plot include the unlikely combination of a former nurse in Banda's medical practice, the head of the Central Bank, described as a Robespierre, and various opponents of the president's leadership, many now dead.

Cecelia Kadzamira, a lively nurse in her mid-forties who towers over Banda, is the president's longtime companion.

She resides with him in his numerous palaces and state lodges and is believed to have complete control over access to the leader. About a decade ago Banda designated Mama Kadzamira, as she is popularly known, Malawi's "official hostess."

The chief antagonist is John Tembo, the suave, nattily attired governor of the Malawi Reserve Bank who has stood by Banda for two decades while a variety of potential successors have stuck their heads out only to have them lopped off.

Tembo, 51, has an advantage unavailable to any other pretenders to the throne: Mama Kadzamira is his niece and thus reportedly puts his case forward with vigor at Banda's Sanjika Palace in Blantyre.

There are many other antagonists--exiles long outside the country who oppose Banda and lately some inside who seem to have become nervous about a Malawi without Banda.

One exile, Attati Mpakati, the leader of a leftist rebel group, was killed in Harare, Zimbabwe, in March. Former justice minister Orton Chirwa and his wife Vera were sentenced to death by a traditional court in May for plotting to overthrow the government from neighboring Zambia and Tanzania.

The story line picked up pace in May with reports, belatedly denied by the government, that the life president was considering a one-year "leave of absence" in which Kadzamira and Tembo would move to the center of power. In another version he simply decided to make his nurse vice president and Tembo prime minister.

Tembo is believed to have many enemies and no political base so it would appear that he could only gain power through Banda.

The drama then moved to center stage in mid-May when three senior Cabinet ministers and a member of the National Assembly died. The government said they were killed in an automobile accident, but it is hard to find a Malawian, other than officials, a diplomat or other foreign resident who believes the government line.

Those killed were Malawi Congress Party Secretary General Dick Matenje, who was also minister without portfolio; Aaron Gadama, minister of the central region; John Sangala, minister of health, and David Chiwanga. All four were members of the National Assembly.

A bulletin on government radio said they disappeared on May 18, the day parliament adjourned for new elections. After a five-day silence on the subject, the radio issued a terse, five-sentence newscast saying the senior officials had "lost their lives as a result of a car accident" on a road southwest of Blantyre near the Mozambican border.

Two days later the government issued a long statement in the Daily Times, the country's main newspaper, which added few details. It said the car was "badly wrecked," having "overturned several times."

The government has refused to provide any further information on the deaths despite widespread reports in Malawi and outside the country that the men were killed for balking at the alleged succession plan.

Suspicions were aroused because there were no state funerals or messages of condolence. The men were buried privately with the coffins sealed. The specific site of the accident has not been disclosed nor has the car been shown, leading to numerous reports that police shot the men and then staged an accident.

Cynics also noted that it is unheard of in status-conscious Africa for ministers to travel together or in an unchauffeured car.

Although similar mysterious deaths of officials have occurred in the past, most reports do not link Banda directly to the alleged killings.

One explanation is that Banda told Tembo he was angry at the rare display of opposition and that Tembo then interpreted the anger "with an excess of zeal." According to this version, the police then either killed the officials as they attempted to escape or else shot them in cold blood and then botched the cover-up attempt.

Although Tembo met informally with some reporters to talk about the economy, he refused to discuss the incident. Another senior official explained his refusal by saying, "I intend to remain employed."

The government made another attempt to paper over the issue in an editorial in its Daily Times newspaper June 17. The editorial stunned many Malawians because for the first time it talked about the succession--a taboo subject. Without mentioning Tembo, it denied the allegations about him but gave no further details. It simply called the rumormongers "followers of Lucifer."

"What the incident tells us," one diplomat said, "is to get to know Tembo and Mama Kadzamira very well." The question, he added, was whether Banda was "losing his grip" on affairs or simply "loosening it."

Most tend toward the latter explanation, noting that in the last couple of years there has been an easing of dress code regulations and of tight censorship.

Yet despite the slight easing of control, Malawians are afraid to talk openly about the situation.

"Not many people believe the government's story" about the officials' deaths, a Malawian said, "but we don't talk much. We are sensitive people."

He concluded the interview by saying, "I hope I will be safe."

Despite the apparent purge, the country is outwardly calm. Twenty foreign correspondents were admitted to cover last week's parliamentary elections and were allowed to go anywhere they wished.

Banda announced a Cabinet shuffle today, following the elections. Most ministers remained in the Cabinet, and although Robson Chirwa, administrative secretary of Banda's party, replaced Matenje as minister without portfolio, the more important post of party general secretary remains unfilled.

Unlike what they experience in practically any other African country, correspondents covering the election did not encounter any roadblocks. No troops or police patrolled the streets of the three major cities of Blantyre, Lilongwe and Zomba, and the residents said none were out at the time of the mysterious deaths in May.

The government, which for years severely curtailed entry of the press, undoubtedly admitted reporters to rebut rumors from exiles that the country was in turmoil. Announcing the presence of the foreign correspondents, a government spokesman said, "We are sure they will find Malawi a haven of peace."

The election was a foregone conclusion since all candidates were handpicked by Banda, even though about half the previous members lost their seats. About 75 of the 101 elected seats were contested, but no campaigning was allowed because candidates "would be tempted to bribe and corrupt people," said parliament speaker Nelson Khonje.

The outspoken Banda alienated the Organization of African Unity in 1966 by saying Africa's "tragedy" was that "too many ignorant people are in a position of power and responsibility." He became Africa's odd man out when he visited South Africa in 1971, making Pretoria his biggest trade partner.

The South Africans financed the construction of Malawi's new half-billion-dollar capital at Lilongwe, and there is little question that Banda's South African connection has helped Malawi just as his firm grip has benefited most Malawians.

Now the question is whether the very stability he used to justify his all-encompassing power will crumble when he leaves the scene. Few people expect major changes before he dies. Aside from the presidency, Banda controls four ministries and reportedly approves all Malawian passport applications and employment permits for foreigners.

Even Banda's enemies grudgingly acknowledge that he is a remarkable man. As a teen-ager he went to South Africa to work in the mines and then continued to the United States, Britain and Ghana, remaining in exile for 43 years before returning to Malawi in 1958 at the age of about 60 to lead the country to independence from Britain in 1964.