When Lucinda Franks started her journalism career in 1968, she was known simply as a “coffee girl,” charged with ensuring that the reporters in United Press International’s London newsroom — nearly all of them men — were adequately caffeinated. Impressing editors with stories she wrote on her own time, she was assigned to cover beauty contests and dog shows.

But Ms. Franks had far greater ambitions. An American expatriate and self-described hippie, she went to Belfast one weekend to march for civil rights on behalf of Northern Ireland’s Catholic minority, then found herself in the middle of a major story after the marchers were attacked by club-wielding Protestants near the Irish border.

“Civil war has broken out here,” she told a UPI editor after finding a pay phone, “and I’ve got the story!” When he replied that women weren’t allowed to cover war zones, Ms. Franks argued that the story would be over by the time a man arrived to take her place. Eventually, the editor agreed. He went on to compliment her work by saying, “Franks, I don’t think of you as a woman anymore. You write like a man.”

For the next few years, Ms. Franks covered the Northern Irish conflict known as the Troubles. Her next assignment, writing about the militant antiwar group the Weathermen back home in the United States, won her the Pulitzer Prize in national reporting at age 24, making her one of the youngest winners in Pulitzer history and the first woman to be honored in that category.

Ms. Franks, who shared the prize with co-author Thomas Powers, called it a “gold-plated calling card for life,” and went on to write for publications including the New York Times and the New Yorker, in addition to publishing well-received memoirs about her father’s secret history as a spy and her passionate, unlikely marriage to Robert M. Morgenthau, the longtime Manhattan district attorney.

She was 74 when she died May 5 at her family’s home at Fishkill Farms, an apple orchard run by her son in Hopewell Junction, N.Y. She had cancer, her family said.

Ms. Franks formed a singular New York power couple with her husband, the scion of a German Jewish family steeped in politics. While he was nearly three decades her senior and “the stereotype of the bourgeoisie,” as she put it, she was an “undomesticated radical” who had once chained herself to a White House fence and poured pigs’ blood on draft documents to protest the Vietnam War.

“I let it all hang out, while he calmly kept it in,” she wrote in “Timeless,” her 2014 memoir about their romance. “He was cautious, steady, a sloop balanced at dead center. I was guileless, eager to take risks, a catamaran racing breakneck through every channel I encountered. While he was aggressively enforcing the law, I had become dedicated to breaking it. The very notion that we should have come together was an oxymoron.”

The couple met in 1973, when Ms. Franks interviewed Morgenthau for a story about government corruption in the Nixon administration, and started going out three years later, when he invited her to a cocktail party hosted by historian Arthur M. Schlesinger Jr. They married in 1977 and remained together for 41 years, until Morgenthau’s death in 2019.

While he became America’s best-known D.A., battling mobsters, killers and crooked executives, she worked as a freelance journalist and wrote four books, including the novel “Wild Apples” (1991), about two sisters trying to save their family’s orchard, and “My Father’s Secret War” (2007), in which she investigated her father’s military service during World War II.

Sparked by the discovery of a Nazi military cap in his apartment, she spent years researching his past. She learned he had been a spy in U.S. military intelligence and was haunted by memories of a concentration camp he had visited, shortly after it was liberated from the Nazis, and of killing an Army friend after discovering he was a double agent.

“Even the most painful moments — as when she throws a particularly harrowing revelation back in her father’s face to score revenge for adolescent resentments — are recounted with unflinching honesty as the military history takes a backseat to the powerful family drama,” Publishers Weekly wrote in a review.

Ms. Franks also profiled Israeli leader Ariel Sharon for New York magazine and spent five months persuading Hillary Clinton to open up for a 1999 interview in Talk magazine, in which she asked the first lady about her husband’s affair with Monica Lewinsky. President Bill Clinton had been “scarred by abuse” from his childhood, Hillary Clinton said, and had committed a “sin of weakness.”

For the New Yorker, she investigated the case of Katherine Ann Power, an anti-Vietnam War radical who went on the run for more than two decades after participating in a robbery that left a Boston police officer dead.

Ms. Franks, who had helped launch a chapter of Students for a Democratic Society while at Vassar College, often returned to stories about the antiwar movement and the legacy of 1960s radicalism.

It was partly because of her background as an SDS organizer that she was assigned to write about Diana Oughton, a 28-year-old Bryn Mawr College graduate who died in 1970 after a bomb accidentally went off at a Greenwich Village townhouse, where she and other members of the Weathermen were building crude explosives.

“I ended up identifying with her so much that I almost tossed my notebook in the trash and joined the groups that shaped her,” Ms. Franks wrote in “Timeless,” recalling the reporting process behind “The Making of a Terrorist,” the five-part series that won her the Pulitzer. “Everything about her resonated emotionally: she was a good woman, educated, sensitive, highly intelligent, and, like me, drawn to making sacrifices for larger causes.”

“I ended up deciding not to join the Weathermen,” she continued, “and to write its story instead.”

Lucinda Laura Franks was born in Chicago on July 16, 1946, and grew up in Wellesley, Mass. Her father was an executive at a metals company, and her mother was a hospital trustee and fundraiser for the Opera Company of Boston. Ms. Franks graduated from the private Beaver Country Day School before studying English at Vassar College.

After receiving a bachelor’s degree in 1968, she sailed to London, disillusioned by the assassinations of the Rev. Martin Luther King Jr. and Sen. Robert F. Kennedy (D-N.Y.). She joined the Times in 1974 and quit the paper after about two years.

Ms. Franks “was still in hippie mode,” as she put it, when she began seeing Morgenthau, whose first wife had died of cancer. In “Timeless,” she recalled that while he generally tolerated her radical politics, he had his limits, requesting an early exit after they visited some of her friends who were using an American flag as a shower curtain.

Survivors include two children, Joshua and Amy Morgenthau; four stepchildren, Jenny Morgenthau, Anne Morgenthau Grand, Robert P. Morgenthau and Barbara Morgenthau Lee; and a sister. A stepdaughter, Elinor Morgenthau, died in 2020.

In a 2017 essay for the Times, published in the early months of the #MeToo movement, Ms. Franks recalled being sexually harassed by male reporters in London and facing the resentment of colleagues after winning the Pulitzer. “I was haunted by the creeping conviction that I didn’t deserve the prize — I should give it back,” she wrote. “For at least the next 10 years, I was too ashamed to tell people I’d won.”

“We, the earliest female newswomen, were tough, ambitious, even cocky about our talent, but over the years, our self-confidence was often irreparably harmed,” she continued. “Our generation might have been smart, but there was much we just didn’t get. Grateful to win a place in the hierarchy of power, we didn’t understand the ways that gender degradation still shaped our work lives.”

Read more: