Hollywood loves the smoke and mirrors of espionage. For decades, it has made a dirty, dangerous business look glamorous on silver screens.

“Bridge of Spies,” the cold-war epic directed by Steven Spielberg, contends for six Academy Awards Sunday, including best picture. The brilliant Briton Mark Rylance is up for best supporting actor. He plays the Soviet spook who the FBI knew as Col. Rudolf Abel before and after his arrest in New York in 1957. Tom Hanks stars as the noble lawyer James Donovan, who defended the mysterious colonel up to the Supreme Court. In 1962, at the behest of the CIA, Donovan handed his imprisoned client over to the Russians in exchange for the captured pilot of a U–2 spy plane shot down over Sverdlovsk. The swap took place at the Berlin bridge connecting communist East Berlin to the West — thus the title.

The movie tries to be true to life. But it reconstructs five grim years in two hours and twenty-one minutes. As it often is, the truth was stranger than its fictional portrayal.

I’ve written on American intelligence over three decades, as a reporter for The New York Times and as the author of histories of the CIA (Legacy of Ashes) and the FBI (Enemies). I see Rylance, an actor’s actor, as the heart of the film. He bears an astonishing resemblance to Abel; his silence and cunning captures the essence of espionage. A gray man in a gray suit slips through the shadows in a black-and-white world carrying encrypted secrets.

Now to the story’s facts and fictions:

J. Edgar Hoover had been on the warpath against Soviet spies for a decade when a drunken KGB courier walked into the U.S. Embassy in Paris in April 1957. Reino Hayhanen feared for his life, having fouled up to a fare-thee-well. He had taken $5,000 intended for the American Communist underground in New York, gone on a bender, and bought a one-way ticket to Paris. The CIA station chief delivered him to the custody of the FBI in New York. After the defector dried out, he gave the Bureau its first deep look inside a Soviet spy operation in the United States. Hoover’s nightmare came to life.

Hayhanen told the agents an astounding story. He had a legend — a false identity — and a forged American passport when he boarded the Queen Mary for New York. He served as a courier carrying money and encoded microfilm messages sent to and from Moscow. Many messages were hidden in hollowed-out coins, secreted in New York’s parks and sidewalks. (A trick nickel makes a cameo appearance in the movie.) Hayhanen named his top superior as the first secretary of the Soviet delegation to the United Nations — who had just left New York, never to return — and his main contact as Col. Abel, alias “Emil Goldfus,” an artist with a studio in Brooklyn.

The FBI’s Edmund J. Birch led a squad trailing the artist. Carrying a hiddencamera in a briefcase outside a Manhattan restaurant, he got a clear shot — “one beautiful picture of his face,” Birch remembered. Haynahen identified the face as Abel’s. The FBI watched the suspect around the clock. He never did anything suspicious. The evidence was hearsay.

The Bureau wanted to make an espionage case but they lacked clues. Hoover was livid. On his orders, without a warrant, and outside the law, his agents grabbed Abel, tossed his apartment, and found extensive evidence of spy craft.

But unless the FBI broke Abel, the illegally seized evidence was likely to be inadmissible in court. He was initially charged under the Foreign Agents Registration Act, the immigration statute that the Justice Department used when an espionage case could not be made.

FBI agents grilled him for more than two years — first in a broiling prison for illegal immigrants outside McAllen, Tex., on the Mexican border, at “a wetback camp, in a wire cage,” said the FBI’s Ed Gamber, who interrogated Abel for six weeks and later testified in court. “He was a gentleman, he was polite; he was a nice guy.” And he never broke. Then teams of FBI agents braced him at the Atlanta federal penitentiary, one of the toughest prisons in the United States. “I’ll talk with you about art, mathematics, photography, anything you want to talk about, but don’t ask me about my intelligence background,” Abel said. “I have not said anything, and I’m not going to now.”

Playing Abel in “Bridge of Spies,” Rylance has a great line eliding that silence in three words. If he cooperated, he asks, “Would it help?” History suggests not.

In real life, prosecutors persuaded a federal judge to allow use of the evidence they had seized. Abel was quickly convicted and sentenced to thirty years. Donovan almost immediately won an appeal before the Supreme Court, which granted an extraordinary 90 minutes for argument. He cited the Constitution’s ban against warrantless searches and jailing, arguing that Abel’s arrest and imprisonment were an affront to American justice.

Anyone who follows the court may be shocked to read that, after long deliberation, only five justices sided with the government. The minority of four wrote: “This is a notorious case, with a notorious defendant. Yet we must take care to enforce the Constitution without regard to the nature of the crime.”

President Dwight D. Eisenhower was outraged. “We would have to expose all our intelligence sources and methods in order to obtain a conviction,” Eisenhower fumed at a National Security Council meeting attended by Vice President Richard M. Nixon in May 1960, seven weeks after the decision– and shortly after the U–2 pilot, Francis Gary Powers, was shot down. “About all the FBI can do is keep spies under surveillance.”

The only thing of import Abel ever said to the FBI was an insult: “American intelligence walks in baby shoes.” And he had a point. Not until the end of the cold war did the CIA and the FBI learn that the man they knew as Abel was an entirely different person.

He was born in 1903 in Newcastle-on-Tyne, England, as Willie Fisher, the son of a Bolshevik. He went to the Soviet Union, became a committed Communist, and was given training, a legend, and a role in Moscow’s spy network before World War Two. He came to the United States after the war and worked in silence, undetected, for nearly a decade. And he lived on for nearly a decade after the great swap, dying on November 15, 1971.

Twenty years on, the Soviet Union itself ceased to exist. And today another colonel trained by its vicious spy service rules in the Kremlin.

Hollywood would never greenlight that movie. No one would believe the script.