It began on a sultry morning in Lagos, Nigeria in February 1984, weeks after a group of military officers had overthrown the country's civilian government. Despite the tense atmosphere in the capital, Jersey City, N.J. businesswoman Marie McBroom, 59, had decided to stay on in Lagos hoping to conclude several deals in foodstuffs and fuel for her fledgling import/ export firm. It proved to be a costly misjudgment.

On February 3, McBroom was seized at gunpoint by members of the feared Nigerian Security Organization (NSO). She was held without charges for nine months, first in an interrogation cell at NSO headquarters, then in the city's grim maximum-security Kirikiri Prison. On November 30 McBroom finally was brought before a four-man military tribunal and formally accused of "conspiring to deal with petroleum products without lawful authority." She pleaded not guilty to the charges. According to Nigerian authorities, McBroom had attempted to negotiate the purchase of crude oil and automotive gas without first obtaining an export license. Under the previous government the offense was considered minor, usually carrying a $1,000 fine. But the new regime has already sentenced 100 people to death for various crimes; under new laws, arson, counterfeiting, heroin trafficking, armed robbery and even telephone tampering are capital offenses. If convicted, McBroom, too, could face execution by firing squad.

Some 6,000 miles from the courtroom where the divorcée is on trial, her daughters Dana Manno and Marcia McBroom Landess, both in their late 20s, are helpless. Their distress began when they telephoned their mother at a hotel in Lagos on February 7 and discovered that she had vanished. "We had spoken to her four days earlier and she said things were going well and that she'd be home in two weeks," says Marcia. "When I called back, a stranger answered her telephone, and the hotel desk said she'd checked out. But it wasn't like her to leave without telling us exactly where she was going. The U.S. Embassy in Lagos first considered us 'alarmists' and said she was probably just out of town on holiday. About two weeks later a friend telephoned from London and said he had heard from sources inside the country that my mother had been taken captive by the NSO."

While the U.S. State Department initiated an inquiry, McBroom's daughters received positive word of their mother's whereabouts in April from Dorothy Davies, 52, another black American commodities broker. Davies had been arrested and incarcerated with McBroom before her captors released her after some 40 days and expelled her from Nigeria. Since then, McBroom's children have spent much of their time in an unsuccessful campaign to win their mother's freedom. In a midtown Manhattan apartment filled with primitive carvings from Ghana, Nigeria and Kenya that attest to her family's long love of Africa, Manno, an actress-songwriter, vents her frustration at the ineffectiveness of phone calls to her mother's lawyer in Lagos and meetings with Nigeria's UN ambassador, Joseph Garba, with Amnesty International and with State Department officials. "We've been living an endless nightmare," she says. The sisters have enlisted the support of clergymen and congressmen, including Senators Daniel Patrick Moynihan (D-NY), Frank Lautenberg (D-NJ) and Bill Bradley (D-NJ), whose letters to the Nigerian government have thus far gone unanswered. The State Department tells them that it is "doing all we can" to free her. "The sense we get is that the Nigerians are independent, and there's a lot of anti-American feeling there now," says Dana.

Richard Weeks, a State Department spokesman, acknowledges that, of the roughly 3,000 cases of Americans imprisoned in foreign countries last year, the Marie McBroom case is "one of the most unusual. We've expressed our concern repeatedly to Nigerian officials—up to the ministerial level—about their failure to notify us of her detention promptly, their failure to allow us prompt as well as regular access to her and their failure to bring charges against her for months," he says. A press officer at the Nigerian Embassy in Washington had "no comment" on either the charges against McBroom or her detention, insisting that "anything I say would prejudice the court." Asked whether the death penalty was too stiff a punishment for illegal oil dealing, he responded: "Any law that we pass is certainly in our national interest."

Meanwhile, McBroom's physical state continues to deteriorate. She has suffered dysentery and malaria. "We've been told she's lost 40 pounds and aged 10 years," says Dana. "We asked the Nigerians in the U.S. for a letter of 'safe conduct' to see her, but they refused, saying that the NSO would not respect the letter, and it is answerable to nobody but itself."

Two weeks ago the McBroom case took another bizarre turn when the sisters began receiving a series of telephone calls from a man identifying himself as a major in the Nigerian army, demanding a payoff of 800,000 naira ($993,920) in exchange for their mother's release. "He called from London and told us, 'We know your mother has money. Just draw a check from your London account,' " says Manno. "I said, 'I wish we had the money to send, but there's nothing there.' " (The State Department would not comment on the alleged ransom demand.)

Marie McBroom grew up in Harlem, the daughter of a carpenter, who died when she was a child, and a seamstress from Montserrat in the West Indies, who was an ardent follower of Marcus Garvey, a Jamaican black nationalist and "Back-to-Africa" movement founder. "My mother grew up with a dream of bringing Afro-Americans in touch with the continent," says Dana. McBroom's work as a secretary at the United Nations in the 1950s introduced her to a number of African diplomats, and after a vacation in Cameroon in 1960, she started a travel agency in Manhattan. In 1980, with the encouragement of Nigerian officials, she launched Palm International Specialties Ltd., an agency headquartered in New York, to export rice, tomato paste and other commodities to Lagos. McBroom was seeking to move into the trade of Nigerian oil, her daughters say, when the coup took place.

Like fellow trader Dorothy Davies, she was caught in an anticorruption crackdown directed at those who had dealt with the previous civilian government. "Nobody ever got oil out of that country unless some deal was going on," admits Davies. "You didn't have to bribe anyone directly, but certain 'commissions' always had to be paid. Even something as small as getting a license to export rice was corrupt." After their arrest, the women were forced to sleep on a filthy carpet with five other prisoners in a 10 x 10 cell and bathe in dirty water. They were denied exercise and changes of clothing. "When I think how terrible those days were," says Davies, "then I think of the months and months she's been in there, I don't know how she's even alive to face trial."

Part of her current torment, Davies conjectures, may be of McBroom's own making. During the 40 days they were locked up together, Davies says, Marie became alarmingly intransigent toward her jailors. "I kept telling her, 'When your hand is in the lion's mouth, you have to tread easy,' but she wouldn't listen," says Davies. "Once I followed out the door a woman guard who said she was going to report Marie's insults to a higher authority. I begged and pleaded with the guard, telling her, 'We're under pressure. Nobody wants to offend you.' I kissed her hand and began crying. She put her arms around me briefly, then pushed me back toward the cell. She never told me she wouldn't report it, but I knew she wouldn't."

The McBroom family is hoping—not unrealistically, according to Ida Lewis, an American journalist who recently returned from observing the tribunal in Lagos—that Marie will be expelled from the country rather than executed after the trial's conclusion. Meanwhile, McBroom's daughters have been forced to shut down their mother's travel agency and are besieged by mounting legal costs and phone bills topping $500 a month. Far worse, they say, has been the shattering of a dream. "It's so ironic," says Dana Manno. "All our lives we've always tried to impress a love of Africa on our kids—and now their grandmother is wasting away in an African jail."