In early March, President Trump sent four tweets accusing his predecessor of wiretapping the phones in Trump Tower in the months before the 2016 election. The tweets were just the latest manifestation of Trump’s preoccupation with eavesdropping and surveillance—one that can be traced back decades. As BuzzFeed’s Aram Roston reported last summer, during the mid-two-thousands, Trump kept a telephone console in his bedroom at his Mar-a-Lago resort, in Palm Beach, that allowed him to listen in on phone calls between his employees and, sometimes, staff and guests. (Trump denied this.) In the mid-nineteen-eighties, Trump allowed Tony Schwartz, his ghostwriter, to listen in on his private phone calls with bankers, lawyers, and developers, as Schwartz wrote “The Art of the Deal.” And, in the nineteen-seventies and eighties, many of Trump’s private conversations with his late mentor, the lawyer Roy Cohn, were eavesdropped on by Cohn’s longtime switchboard operator and courier, whose activities were later exposed.

Cohn, who had been an aide to Senator Joe McCarthy, in the nineteen-fifties, was a political fixer and lawyer who represented New York power brokers, from the Yankees owner George Steinbrenner to the mob boss Carlo Gambino. Trump was one of his favorite clients; before Cohn’s death, of AIDS-related complications, in 1986, the two men talked up to five times a day and partied together at Studio 54 and other night clubs. “Roy was brutal, but he was a very loyal guy,” Trump told the writer Tim O’Brien, in 2005. “He brutalized for you.”

Christine Seymour had recently graduated from Sarah Lawrence College when she started working at the back of Cohn’s office as a switchboard operator, connecting calls with clients including Nancy Reagan, Gloria Vanderbilt, and the mobsters Gambino and Anthony (Fat Tony) Salerno. “She listened in to all of them,” Susan Bell, Cohn’s longtime secretary, recalled recently. “Not at his direction, but he knew.” A pretty brunette, Seymour was, according to her brothers, brash and funny, with a gossipy sense of humor. Cohn had his reasons for tolerating her behavior. “She was very efficient, and he liked that about her,” Bell said. “She would work anytime, day or night. She was always at his beck and call.”

After Cohn died and his law firm dissolved, Seymour left the city and moved to Florida. She settled in Key Colony Beach, a sleepy town at the bottom of the Keys, where, in the early nineties, she started writing a book, “Surviving Roy Cohn,” based on her notes on the eavesdropped calls. It must have seemed an ideal moment for a project that promised to take the reader inside the town house of one of the most scandalous figures in recent New York history. In 1993, James Woods was nominated for an Emmy for his portrayal of Cohn in an HBO biopic, “Citizen Cohn,” and “Angels in America,” Tony Kushner’s play dramatizing Cohn’s struggle with AIDS, had débuted to acclaim on Broadway.

On the morning of May 5, 1994, the New York Post ran a column by Cindy Adams with the headline “Savvy Chris Spills the Beans on Roy Cohn.” In her characteristically breezy manner, Adams wrote about Seymour’s book project, listing the secrets she would expose. (“How a porno flick was filmed in the office and business was conducted while someone was being whipped”; “How Sen. Joe McCarthy hid the fact that he was gay. . . .”) “Chris taped conversations,” she wrote. “She kept a log—three spiral notebooks a day—of transactions.” Adams wrote that Seymour “monitored every call in or out, knew everything, everyone, knew where all the bodies were buried.” The story ricocheted through the city, and Cohn’s former law partners and staffers received phone calls from several other anxious clients, worried that their secrets would be revealed.

Five months later, on October 20, 1994, Seymour was driving her blue two-door Yugo on a highway in Florida at dusk when she collided head-on with a tractor-trailer and was instantly killed. She was forty-six, and the book was still unfinished. Seymour’s collaborator on the book, an author and literary agent named Jeffrey Schmidt, was at home on Long Island when he got the call from Seymour’s mother, Adele, who lived in nearby Shoreham. As he recalled recently, on hearing the news of Seymour’s death, he panicked, took a box of the notebooks, and burned them.

As for the recordings, none of Cohn’s former employees can confirm that Christine made any. But Christine’s brother, Brian, who once worked as a crew member on Cohn’s eighty-foot yacht, Defiance, told me that when Christine moved to Florida, she had handed him three small reel-to-reel tapes that she claimed she had made. The tapes were, he recalled, “in god-awful shape, spooled and unspooled and crinkled.” He stored them in his mother’s attic, where he later found them, in 2009, after she passed away. “We just tossed them in the trash,” he told me. In the spring of 1995, Schmidt told the syndicated columnist Liz Smith that some tapes still existed and would soon be the basis for a Broadway musical, written by Seymour and Schmidt, with music by Jeanette Cooper. “Nothing Sacred” is really Seymour’s story; her eavesdropping is at the heart of the drama. The play kicks off with Cohn’s voice “heard over the telephone wire.” On one of her first days, she tells a colleague that Cohn is on the phone with Nancy Reagan, adding, “Oh, I wish I could hear what they’re saying.” The office manager replies, “Go ahead and listen. Roy doesn’t mind.” Later, she adds, “Some of the most important conversations of the twentieth century have come through the switchboard. And they’re all on tape.” One of the first songs includes the line, “This damn phone, needs a chaperone / Someone who’ll defend, the fortress of a friend / In exchange she’ll learn things she would never know.” After one staged reading of “Nothing Sacred,” in the winter of 1997, at the Dicapo Opera Theatre, on the Upper East Side, Schmidt got caught up in other projects, he said, and the play was never produced.

Schmidt still lives in Stony Brook, on Long Island, where he runs NYCreative Management, a literary agency. Last September, we met at the Strand one afternoon and then walked across the street for a cup of coffee. It was a warm afternoon, but Schmidt was wearing a black suit with a bright yellow tie. He handed me a yellow packing envelope, containing “some things left behind in Roy’s office.” Inside the envelope were several floppy disks, a cassette tape, the “Nothing Sacred” screenplay, a 1981 invitation to a Ronald Reagan Presidential Inauguration party, the consent form to participate in an AIDS drug trial, a few faded photographs, and dozens of notes, some of them stained, written in Seymour’s hasty longhand. The notes contain lists of the clients who called Cohn’s office, including their personal phone numbers; Seymour’s reminiscences of her experience working with Cohn, including lunch orders for pepper-sausage-and-mushroom pizza slices; and her description of Cohn’s conversations with Trump, Steinbrenner, Vanderbilt, and Nancy Reagan, among others, and what appear to be direct quotes from some of those phone calls—although it’s almost impossible to know how much of Seymour’s account in the notebooks and script is true.

Some of the Roy Cohn-related documents that are still in Jeffrey Schmidt’s possession, including the handwritten notes of Cohn’s switchboard operator, Christine Seymour. PHOTOGRAPH BY JOSÉ GINARTE FOR THE NEW YORKER PHOTOGRAPH BY JOSÉ GINARTE FOR THE NEW YORKER

One of Seymour’s notes describes Cohn’s efforts to advance the judicial career of Trump’s sister, Maryanne Trump Barry, who served as a federal appeals-court judge for decades, until stepping down soon after Trump assumed the Presidency: “Roy got the White House to give her her judgeship,” Seymour writes. “Roy was out and the call came in to tell her she got it. I took the call and called her to tell her. Ten minutes later, Donald called to say thank you.” (Barry did not respond to requests for comment.)