To her, it looked like a harmless piece of coal, about the size of her fist. She remembers passing it to a Chinese secret agent. She remembers later learning about the train, the bridge, the explosion. Sometimes she thinks she has suppressed many wartime memories, but even after almost 70 years, they can creep back.

Betty McIntosh, 96, says that is part of being a spy: the doubts about whether you did the right thing, and hearing about those who died because of what you did, and whether you had alternatives. But it was a war.

Her friend Doris Bohrer would understand, but even so, McIntosh still hasn’t divulged everything about every World War II mission. Even though it turns out that Bohrer, 88, was an operative in the war, too: OSS, then CIA, just like McIntosh.

To most other residents of the retirement community in Northern Virginia, these two elegant, well-coiffed widows, Betty and Doris to everyone, are just part of the anonymous parade of aged men and women who play mixed bridge and talk about the brand-new heart and vascular center down the road, the day’s menu at the dining hall, and their pets.

What a curious resolution to it all: that although their paths never crossed during their undercover careers, McIntosh and Bohrer would find each other here, neighbors on the same street in the Westminster at Lake Ridge seniors village in Prince William County. Two women who wear the wedding rings of their dead husbands. Two women who laugh like girls when they reminisce, who are nearly inseparable.

McIntosh says she calls Bohrer almost every morning, just to make sure she’s still alive. Bohrer, for her part, can still drive and runs errands for her friend, who is, after all, eight years older and finds it less easy to get around.

“How’s it doing today, Betty?” Bohrer asks one recent weekday, stepping inside McIntosh’s living room, where paintings by a Japanese prisoner of war hang on the wall. Bohrer was bringing some medication for McIntosh, who had just had two teeth pulled.

“You’ve got the temperature setting in here at ‘off.’ You need it on ‘cool,’ ” Bohrer instructs McIntosh. “I’ve done that. Easy to do.” She adjusts the thermostat.

“What would I do without you, dear?” McIntosh says.

* * *

It was the early 1940s when Bohrer and McIntosh fell into jobs at the Office of Strategic Services, the nation’s first intelligence agency, created by President Franklin D. Roosevelt and led by William “Wild Bill” Donovan, a Wall Street lawyer and World War I veteran. They were among the rarest of operatives, women working overseas during World War II.

In China, McIntosh, a “black propaganda” specialist, whipped up fake news stories to undermine the morale of the enemy — including an effort to convince the Japanese emperor’s soldiers that their wives were procreating with other men back home. Stationed in Italy, Bohrer analyzed aerial photographs of Germany, helping select sites to air-drop and rescue OSS officers behind enemy lines.

Bohrer, a Montgomery Blair High School graduate who yearned to fly airplanes, wanted to defend the country from another Pearl Harbor attack. So in 1942, she took the civil service exam.

She passed. The first call came from the OSS, and to this day, Bohrer does not know why. The job: typist. She took it. At first she typed up intelligence reports. In 1943, her superiors promoted her.

Working in an office known as the “Q Building” in Foggy Bottom, Bohrer analyzed aerial photos of Europe and created sophisticated relief maps of Sicily using balsa wood. At the age of 20, she was helping plot the Allied invasion on the Italian front and eventually wound up stationed on the country’s Adriatic coast.

“It was an interesting way to look at the world. It was almost as good as flying. You’re looking over people’s shoulders,” she reflects today. “Maybe I am nosy.”

* * *

At the same time, elsewhere in the Q Building, McIntosh launched her OSS tenure.

McIntosh, then in her late 20s, had been a newspaper and wire service reporter in Hawaii and Washington. She grew up in Honolulu, attended the Punahou School (where a future U.S. president would one day be a student) and was the goddaughter of Washington Senators baseball legend Walter “Big Train” Johnson. (Her father, William Peet, was a well-known sports editor for the Washington Herald.)

She knew Japanese. She wanted a job overseas. She and other reporters in the Scripps Howard bureau in Washington were growing jealous of their colleague Ernie Pyle, whose war dispatches made him an American folk hero.

One day in 1943, while she was covering an event at the Department of Agriculture — reporting on an exhibit showcasing new sleeping bags lined with chicken feathers — an OSS official approached her.

Are you interested in a secret overseas assignment for the government? he asked.

Why yes, she was, she replied. Soon the reporter eager for foreign travel was casting off her press credentials and filling out paperwork in the mysterious Q Building. McIntosh learned to shoot a .32-caliber pistol at an OSS training facility in Bethesda that is now Congressional Country Club. She took an oath never to reveal the agency’s secrets. If anyone asked what she did, she was to tell them she was a file clerk.

In reality, McIntosh was a propagandist who worked for one of the OSS’s quirkier branches: Morale Operations. Its operatives would live overseas and concoct fake but authentic-sounding rumors, news stories and radio reports to make the enemy citizenry think their troops were losing and that they should give up.

“The man who got me hired said the work would be quite interesting and promised I wouldn’t be disappointed,” McIntosh says. “He was right.”

* * *

Just past noon, the women meet at the Westminster dining hall. Bohrer jokingly calls it “the Big House,” but it’s hardly institutional. They sit at a white-clothed table, where a waitress takes their orders. Bohrer gets the barbecue sandwich. McIntosh likes the mahi-mahi. The room is filled mostly with women.

“I am fascinated with what you did,” McIntosh begins. “What’s the story about the bombs?”

“No! Grenades!” Bohrer says.

Bohrer recalls how, during her OSS posting in northern Italy with an Air Force division, she played a prank on several servicemen who had been mocking her for some reason or another. To get back at them, she dropped a disabled grenade onto their mess hall table.

“They cleared the tables and went out the windows,” she says, before cocking her head side to side and quipping about her fellow senior citizens: “They’re not as agile. And they wouldn’t even know a grenade if they saw one.”

After the meal, they head to Bohrer’s sunny two-bedroom cottage. Bohrer picks through an old trunk of OSS documents, and letters from a former suitor and her father. Her memory of some missions returns instantly: She used aerial photographs to gather intelligence on the Nazis’ movements and what they were building.

“That’s how we knew where the concentration camps were located, but we were too late,” she says. “We kept wondering where all the trains were going. The Germans were also building rocket and electronics factories. We watched what went in, what went out.”

One stapled package of papers is titled “Operation Wowser: The participation of heavy bombers in final victory in Italy.” A tiny yellowed envelope contains four black-and-white photos of the bloodied corpse of Italian dictator Benito Mussolini.

“It was of interest to us for some reason,” she says, sounding frustrated. “I can’t remember why I kept it. It must be of some significance.”

McIntosh, sitting in a corner, is curious about something else.

She eyes Bohrer’s trunk and says, “Where are all the love letters?”

The two of them start cracking up. “I’ve got nothing juicy,” Bohrer says.

* * *

Being one of “Donovan’s Girls” — and everyone called them girls then — required a certain independence and willpower to succeed in such a male-dominated work culture.

“We were neglected. We had no privacy. Down the hall, there was a bathroom with no running water,” Bohrer says of her OSS days. “We couldn’t bathe or do our hair well. The guys all had their own rooms.”

McIntosh nods. “There were hardly any women in Morale Operations,” she says.

“That’s too bad. Women are good. They’re more devious,” Bohrer says.

The two never met at the OSS headquarters in Washington, but they both remember its cafeteria. The slow-moving fans. Meals for 50 cents. Fresh pies.

“It was so hot, you thought you were going to die,” Bohrer says. “We were probably in the cafeteria line together.”

“But you didn’t really mix with people,” McIntosh says. “You wouldn’t know what to talk about. I couldn’t talk to you about Morale Operations. And I wouldn’t understand your maps.”

Once McIntosh graduated from OSS training, she set off for India. In a 1947 memoir, “Undercover Girl,” she recounted her exploits and those of other “morally tough, physically attractive spies,” as a reviewer in the New York Post put it. The reviewer added: “This is probably the most revealing picture of female nature since Clare Boothe Luce wrote ‘The Women.’ ”

That era remains fresh in her mind. One of her first missions was to forge and distribute a realistic Japanese government order to its soldiers in Burma. The directive permitted soldiers to surrender and demand fair treatment if they were outnumbered or caught, and rescinded the prevailing order that they should fight to their deaths.

McIntosh typed up the forgery and had a Japanese POW write the order in calligraphy to bolster its verisimilitude. Then she passed it to a Morale Operations team, which handed it to a Burmese OSS agent.

The agent killed a Japanese courier, McIntosh says, and stuffed the order in the dead man’s knapsack.

“Then the Burmese agent went to the Japanese and said, ‘Get your man.’ And the Japanese went through his knapsack and found the new order,” McIntosh says, smiling. “At the end of the war in northern Burma, there were lots of surrenders.”

Soon, McIntosh was hurtling toward China with the future famous chef Julia Child in a flight so turbulent she believed they both were going to die. Once they landed, McIntosh carried on the same tactics, but one mission seemed more unusual than most.

It is a story she’s kept mostly to herself, had not told Bohrer, and never disclosed in “Undercover Girl” or her other book, a 1998 work on the agency’s female officers, “Sisterhood of Spies.”

It is a story she was ordered never to reveal: the time she unwittingly participated in a plot to kill Japanese soldiers with an explosive.

* * *

After the war ended in 1945, President Harry Truman disbanded the OSS. McIntosh and Bohrer both heard about the formation of the Central Intelligence Agency and wound up getting hired there — Bohrer in the 1940s and McIntosh in the 1950s. Both stayed until the 1970s.

To this day, the CIA is the single subject the women do not discuss publicly or with each other in great detail, fearing that disclosures could endanger people they once worked with.

Bohrer worked in the CIA’s Frankfurt station, writing intelligence reports based on her office’s interviews with German scientists who had been kidnapped by the Soviets during the war.

Later she returned to Washington, serving as the agency’s deputy chief of counterintelligence, training CIA staffers about the Russian and German intelligence services. Her husband, Charles Bohrer, whom she met shortly after the war, became the CIA’s director of medical services.

McIntosh’s time in the CIA is more of a mystery; she was sworn never to disclose the work she did there.

McIntosh outlived three husbands. Her first, Alexander MacDonald, was an OSS agent stationed in Burma, and the distance triggered an amicable divorce; later, she married Richard Heppner, a former senior OSS official who went on to work at the Pentagon. He died of a heart attack in his office. In the 1960s, on a CIA assignment in Japan, she met Fred McIntosh, an Air Force pilot, and they soon married.

The couple retired and moved to Leesburg. Fred died five years ago. And soon McIntosh, after 45 years of marriage, needed a more manageable place to live by herself. In 2007, she reached out to a CIA friend, Murray Minster, a widower who was living at the Westminster. He recommended the community to McIntosh because it allows pets, and its cottages offer a sense of independence.

Meanwhile, after her retirement from the agency, Bohrer became a real estate agent. By 2009, her husband had died, and she sold their Alexandria home. She, too, was a good friend of Minster, and she also followed his strong recommendation that she move to the Westminster.

Neither the women nor Minster can recall the exact moment the two met at the retirement community. The friendship was forged over scattered meals in the dining hall, at the local Chinese joint, or while they shopped for pet food (Bohrer has a champion standard poodle, Aria, and McIntosh a cat, Nekosan — “Mr. Cat” in Japanese.)

“Once they moved in here, I got them together, and then came all the questions,” recalls Minster, a former CIA operations officer who worked at the agency for 32 years. “It’s just one of life’s 45 billion coincidences, I guess.”

* * *

In McIntosh’s cottage one late afternoon, the talk turns to the ambivalences that so many soldiers bring back from war.

“Betty, did you worry about the Japanese? Did you feel guilty about something you had done to kill the Japanese?”

McIntosh glances out to her deck, where hungry geese had gathered and are pecking at the window. “Writing the Morale Operations material was fun, in a way,” she says, before drifting into silence.

There was something left unsaid, but something she felt the need to unburden herself of. At a different time, alone, McIntosh admits to feeling the most conflicted about delivering what she thought was a chunk of coal to an Chinese OSS operative at a railway yard near the city of Kunming, in the country’s south. Shortly after the OSS dissolved, she began dating Heppner, the former high-ranking OSS official who would later become her second husband.

“I told him, ‘The only mystery from my time in China is why I delivered the coal,’ ” McIntosh recalls. “He said, ‘I’ll tell you why.’ ”

The “coal” was one of the OSS’s more famous gadgets, called “Black Joe,” and was packed with dynamite, she learned. The Chinese operative took the bomb and boarded a train full of Japanese soldiers. Then the agent waited for the train to head toward a bridge over a lake.

“And then the agent threw the coal into the engine, jumped out, and as the train crossed the bridge, the train exploded,” McIntosh says.

Most of the soldiers were killed.

“I felt very badly. I felt that this one piece of coal that I was responsible for killing all these men,” she says. Then she reconsiders: “Well, not really. I was just the one who handed it to the guy who did the job.”

Then the old spy goes silent again, and stares ahead for a few moments, waiting for her friend to arrive.