Ellis A. Cohen’s script, called “The Secrecy,” is about Elizabeth P. “Betty” McIntosh, one of the country’s most legendary female spies. (Jonathan Newton/The Washington Post)

Ellis A. Cohen was shopping at a strip mall in Maryland about 2½ months ago.

“I can’t say where,” Cohen said.

A lot of conversations with the true crime author, novelist and Hollywood producer go like this.

A mysterious man started walking toward him.

“He had on a button-down shirt, jeans and sneakers,” Cohen said. “He says, ‘Your screenplay with the Central Intelligence Agency that has been embargoed has been lifted.’ ”

McIntosh, seen in 2011 in Woodbridge, Va., served in the nation's first espionage agency, the Office of Strategic Services. (Katherine Frey/The Washington Post)

Cohen was startled. How could a random bystander know about his script collecting dust?

Then, Cohen recalled, the man mentioned a sensitive scene. “When he said that, I believed him, because the only other people with the script were Betty and the CIA. I said, ‘Is there anybody I’m supposed to call?’ And he just walked away. I didn’t follow him.”

Betty is Elizabeth P. “Betty” McIntosh, one of the country’s most legendary female spies. The two had begun working on a screenplay about her life more than a decade ago. But she called a halt to it. She said the CIA didn’t want the movie made.

But McIntosh died a year and a half ago at 100. And then the man approached Cohen in the mall. He took it as a sign that it was okay to revive “The Secrecy,” his screenplay based on interviews with McIntosh about her days during World War II with the Office of Strategic Services (OSS), America’s first centralized spy agency.

Cohen has hired the Baltimore law firm Wright, Constable & Skeen, which is helping him find agents and legal representation in California.

The 71-year-old said he no longer fears the CIA.

His script depicts how McIntosh supposedly learned that Japan might have tried to obtain nuclear material during World War II.

It’s not clear why she would have taken the script to the CIA for approval. The CIA is legally allowed to redact the written works of current or former agency employees and contractors — not journalists or Hollywood screenwriters who have never taken Langley’s secrecy oaths.

Maybe McIntosh felt obligated to take the script to the CIA since she told Cohen so much about her spy life, he said.

Or maybe what she had to say was not quite accurate. OSS and nuclear history experts are skeptical of the things Cohen says McIntosh told him.

A CIA spokesman declined to comment, citing a general rule that it does not discuss cases that may or may not have gone before its Publications Review Board.

Cohen, who produced the television movies “Dangerous Evidence” (1999) and “Love, Mary” (1985), said he is just relieved he can try to put “The Secrecy” on the big screen. For years, he has been stewing over the proliferation of espionage tales that have surfaced on television, often with the consultation of the CIA, while his project languished.

“When I saw ‘Homeland’ debut, I got really ticked off. It seemed like it was sanctioned by CIA, and I am sitting here waiting around,” Cohen said inside his apartment, where the walls are plastered with old news clippings about his Hollywood heyday and photographs of him alongside actors and artists such as Tennessee Williams, Dustin Hoffman, Sammy Davis Jr. and Faye Dunaway. “I went through a very frustrating period. I never knew whether to take Betty seriously when she said my movie had ‘classified’ information. I didn’t know if she was trying to make me disappear. I asked, ‘Is there anyone I can call at the agency? She always said, ‘No, dearie.’ ”

Cohen said he began talking on the phone with McIntosh shortly after the 1998 release of her second memoir, Sisterhood of Spies.” He’d met her publisher at a book fair in Washington and expressed interest in turning McIntosh’s life into a movie.

From 1999 to 2004, Cohen and McIntosh talked over the phone, and he visited her once at her home in Loudoun County, Va. The juiciest nugget in his script?

McIntosh said she and two other OSS officers, based in New Delhi, were out for a Japanese meal in late 1943 or early 1944 when she overheard a Japanese businessman tell his colleagues about their country’s plans to build a nuclear weapon with uranium-235.

Then-OSS chief Gen. William “Wild Bill” Donovan, acting on McIntosh’s intelligence, convened his aides and Lt. Gen. Leslie Groves, the director of the Manhattan Project — the Allied effort to build a nuclear bomb — and made a stunning declaration: “Now we can confirm Albert Einstein’s assumption of a [Japanese] superbomb . . . and they have been using poor Indian peasants who have been smuggling German uranium-235 or U-235 over the Hump into Burma. From there, the [Japanese] have been using fishermen to carry the U-235 back to Tokyo.”

“Based on what Betty told me, Groves hurried up the Manhattan Project because of her discovery,” Cohen said. “Betty claimed this upset the CIA. She said it was still classified information.”

The story sounds “dubious” to Alex Wellerstein, a nuclear historian at the Stevens Institute of Technology in New Jersey.

“I’ve looked in some detail at the Manhattan Project’s intelligence files, and I have never heard of any kind of overland transfer of uranium,” Wellerstein said. “In general, the United States has no indications during the war that Japan was interested in nuclear technology and did not assume they were capable of pulling off the work involved. We know why the Manhattan Project accelerated — it was due to entirely separate kinds of circumstances.”

Cohen says he checked her story out with other OSS officers, including Eloise Page, Donovan’s secretary, who died in late 2002, and Edwin Putzell, Donovan’s executive officer, who passed away in late 2003.

Still, Douglas Waller, the author of the 2011 biography of Donovan, is extremely skeptical. “A Japanese businessman in New Delhi would have nuclear weapons information that someone like Betty — who worked in propaganda — would overhear? And it would get back to Donovan? I saw no cable traffic on that,” said Waller, who reviewed more than 40,000 pages of OSS messages and other material for his book.

But Cohen is moving forward with his screenplay, despite the naysayers.

In October, his lawyer contacted The Washington Post with a jubilant news release: “The Central Intelligence Agency recently gave a go-ahead to my client’s embargoed screenplay,” his attorney J. Neil Lanzi declared. “Ellis A. Cohen was prohibited from showing or selling or producing ‘The Secrecy’ as a motion picture.”

Now it appears he has a green light.

And should “The Secrecy” ever go into production, Cohen will face a tough call: Who plays McIntosh?

“It’s not kosher to drop a name,” Cohen said, laughing. “But I can say this: someone like Jennifer Lawrence.”