On April 25, 1983, Stern magazine—the German answer to Life—held a press conference to make a sensational announcement: their star reporter had discovered a trove of Hitler’s personal diaries, lost since a plane crash in 1945. Now Stern would begin publishing what he’d found.

The magazine claimed that the diaries—of which, remarkably, there had been no previous record—would require a major rewriting of Hitler’s biography and the history of the Third Reich. The handwritten volumes included everything from descriptions of flatulence and halitosis (“Eva says I have bad breath”), to an account of Braun’s hysterical pregnancy in 1940, and the revelation that a surprisingly sensitive Hitler didn’t know what was happening to the Jews.

Two weeks later, the diaries were exposed as fakes—and not particularly good ones, written at great speed by Konrad Kujau, a small-time crook and prolific forger.

Thirty years later, the Hitler Diaries hoax is still the biggest scandal to have hit German journalism after 1945. Recently, Die Zeit published a “diary of the diaries,” written shortly after the debacle, by Felix Schmidt, one of Stern’s three editors-in-chief at the time (and the only one of the three still living).

Schmidt’s account joins a host of film documentaries, books, court cases, and the 1992 satirical film “Schtonk!” in trying to make sense of what happened. The story of the scandal is fascinating, not least because it reflects a mindset about the Third Reich that seems somewhat remote in today’s Germany. In recent years, Hitler has been surfacing in popular culture as a comedic buffoon, the butt of a dark joke—the kind that emerges with historical distance. (“He’s Back,” a satirical novel about Hitler waking up in present-day Berlin and becoming a media star, just hit No. 1 on the best-seller list; a popular TV show has a recurring sketch in which a bumbling Hitler plays the Steve Carell role in a twisted version of ‘The Office.’)

If today’s Hitler-as-laughable-idiot causes discomfort, the idea of a Hitler who kept diaries seems, in Schmidt’s account, to have inspired a kind of collective insanity in the upper echelons of Stern’s editorial offices thirty years ago.

“It is the 13th of May, 1981,” begins Schmidt’s text. “I’ve been editor-in-chief—one of three—of Stern for some four months when I ask my secretary to get Gerd Heidemann, a journalist in the contemporary history section, in my office within half an hour. Heidemann, a man seldom to be found in the newsroom, who often disappears for weeks without leaving any indication of his destination or contact address, once again cannot be found.”

Heidemann was considered one of the magazine’s best sleuths, despite his well-known weakness for anything having to do with the Nazis; his collection of Nazi memorabilia included Goering’s yacht, where Heidemann socialized with former S.S. officers. At the time, the reporter—who was also said to be romantically involved with Goering’s daughter, Edda—appeared to be somewhat unhealthily fascinated with the Nazi era; he claimed that he was merely cultivating sources. After the scandal, however, he was accused in print of having been an actual Nazi sympathizer.

Schmidt wanted Heidemann to go to Turkey to report on an attempted assassination of the Pope. Before he could track him down to give him the assignment, Schmidt writes, he and the other two chief editors, Rolf Gillhausen and Peter Koch, were called into the office of the magazine’s publisher, where a half-dozen notebooks lay on the table. These, they were informed, had belonged to Hitler. (Mistaking the Gothic “F” for an “A,” Kujau had accidentally labeled each notebook’s black cover “FH” instead of “AH,” a detail that failed to put anyone on alert.) Heidemann and another editor had been dealing with the publisher in secret. Schmidt, Koch, and Gillhausen were not amused, but were drawn into the story nonetheless: it was a major scoop. And the publishers had already sunk as much as a million Deutsche marks in the purchase.

At a next meeting, Heidemann himself explained the origins of his momentous find: in April, 1945, an airplane carrying items belonging to Hitler crashed near Dresden. The diaries, said Heidemann, were among them. The books were hidden by local farmers and later safeguarded by a high-ranking G.D.R. officer. This officer now wanted to sell. “The story of the crash is verifiably true,” writes Schmidt. “This makes Heidemann’s supposed discovery downright believable. However, diaries, as we now know, were not on board.” The G.D.R. officer didn’t exist either, as it turned out.

Next, Heidemann recounted how he had gotten hold of the diaries: on an East German transit highway, the books were thrown from a moving G.D.R.-model car into the open window of his Mercedes, after he had tossed over the money to pay for them. This method, however, struck him as too risky: in the future, the diaries would be smuggled across the border with a piano transport. “Admittedly: we listen intently to Heidemann’s story,” writes Schmidt, “and we are not unimpressed.”

Heidemann cannot reveal the name of his East German source: “If we start digging around, we’ll blow his cover. The man is in danger.”

“Who,” asks Schmidt, “wants to be the one who blows a story like this?”

While Heidemann continued to buy volumes (there were supposedly twenty-seven of them), two historians began a nearly-two-year-long project of verifying the diaries. (Unfortunately, they failed to notice that the history book they were using to check the diaries’ facts—Max Domarus’s anthology, “Hitler: Speeches and Proclamations 1932-1945—The Chronicle of a Dictatorship”—was the same one Kujau had copied swaths of information from, word for word.) Secrecy reigned. Suggestions that Heidemann might be pocketing some of the money were met with hostility. (In the end, a Hamburg court found that Heidemann kept at least 4.4 million Deutsche marks for himself.) When those who knew of the diaries visited the reporter’s apartment, they took his collection of Hitlerania as further proof of the diaries’ authenticity (some of which was supplied to him by Kujau and also turned out to be fake). Heidemann started telling other reporters that Martin Bormann, Hitler’s private secretary, was still alive, and that Bormann thought of Heidemann as a “kind of Parsifal.” “Even after this,” writes Schmidt, “it occurred to no one to wonder about the state of Heidemann’s mental health. The ‘Hitler Diary Euphoria’ had taken hold of all of us.”

In April, 1982, the editors-in-chief learned that far more than twenty-seven diaries existed. “The ‘Fuhrer’ was increasingly communicative,” writes Schmidt. “The notebooks were growing fatter—and getting more and more expensive.” All in all, Stern’s publisher spent 9.3 million Deutsche marks to acquire some sixty volumes. The editors showed examples from the diaries to handwriting experts in New York and Bern—but the comparisons they provided were drawn from Heidemann’s archive and had also been forged by Kujau.

By early 1983, things were moving along at a rapid clip. The publishers began meeting with international outlets—Newsweek, Time, the Times of London, Paris Match—to syndicate the diaries. Well-respected historians, including Hugh Trevor-Roper, were sent by the syndicating papers to Switzerland, where the diaries were locked in a Swiss bank. They declared the books authentic. It was all systems go. (Only Heidemann begged for more time: he had learned that among the still-unclaimed papers was an opera written by Hitler, and the third volume of “Mein Kampf.”) Shortly before the diaries were printed, Schmidt told a friend, “If we’ve been taken in by a fake, then the deepest part of the Alster isn’t deep enough for us.” (Hamburg lies on the river Alster.) On April 22nd, the chief editors tried in vain to get Heidemann to reveal his source. That night, when the reporter came by his office, Schmidt writes, “I try one more time. I give him plenty to drink—maybe that will loosen his tongue. Heidemann says: ‘Mr. Schmidt, you know that lives hang in the balance. I gave my word that I would keep silent.’ ”