The Cuban missile crisis of 1962 is one of most harrowing—and well-studied—moments in modern world history. But exhaustive reporting by Sean D. Naylor, national security correspondent for Yahoo News, reveals that the prologue to the familiar timeline of events has been left out, along with several key players in the saga.

The boilerplate narrative of the Cuban missile crisis goes something like this. During a routine flyover of western Cuba in October of 1962, a U-2 spy plane captured grainy images of what appeared to be a Soviet missile base under construction. Before blowing the whistle on the Soviet Union for setting up nuclear missiles just 90 miles off the coast of the U.S. in violation of international agreements, President John F. Kennedy wanted definitive proof that medium and intermediate-range nuclear missiles, capable of hitting U.S. cities, were indeed present. So on October 23, 1962, a Navy RF-8 Crusader equipped with five reconnaissance cameras swooped over the island nation at low altitude, collecting intelligence on the base.

The public release of the images led to a dramatic standoff, with the United States setting up a naval blockade of the Soviet-aligned island. The Cold War incident ended with the Russians agreeing to dismantle and remove the missiles from Cuba, while the U.S. indicated it would dismantle and remove its medium-range Jupiter nuclear missiles based in Turkey at a later date, though the act could not be seen as "part of any public resolution of the missile crisis," according to the U.S. Department of State's account of events.

But Naylor reports for Yahoo there's an entire chapter that takes place before these events. The missiles and base were actually detected months before the standoff by a covert Miami-based network set up by CIA official Tom Hewitt. After fighting his superiors to approve the operation, in March of 1962 Hewitt slipped a two-man team of exiled Cuban nationals, Esteban Márquez Novo and Yeyo Napoleon, who he had trained himself, up Cuba’s San Diego River via canoe. Back in Cuba, the two set up an underground spy network in the region of Pinar del Río, feeding back intelligence reports to Hewitt.

On August 1 of that year, the team’s agents reported an unusual Soviet vessel docking at a nearby port. No one, not even customs agents were allowed near it, and its contents were carefully unloaded into covered trucks. While the team said they believed they might be unloading nuclear warheads, the CIA was not convinced.

Meanwhile, U-2 plane flights over Cuba were halted after an August 29 trip documented surface-to-air missiles in the area, the same type that infamously shot down American pilot Gary Powers’ U-2 plane over Soviet airspace two years earlier. The administration did not want to risk a similar incident, and halted U-2 flyovers.

That made Hewitt's agents role on the ground all the more crucial. By the middle of September, they reported more Soviet personnel and secret operations taking place in central Pinar del Río in a trapezoid-shaped area bounded by four villages. Eventually, intelligence officers convinced the president to allow a U-2 mission of the trapezoid on October 14, when the first grainy images of the missile base were captured. That led the first Crusader flight and over 100 missions afterward, which searched out Soviet nuclear facilities across the island.

Without the operatives on the ground, the base may not have been discovered when it was, and could have even been operational before it was detected.

So why were Hewitt, Novo and Napoleon and their network's crucial involvement left out of history? Naylor reports the Kennedy administration crafted a narrative that the U-2 found the missiles to protect their in-country network that continued operating in Cuba until it was unraveled by the Castro regime in 1964. Novo, who hoped to spark an uprising on the island, either killed himself when security forces approached his hiding spot or when he learned of his nephew’s death in a battle with security forces.

For his part, Hewitt kept mum about the operation and never went public with his story before his death in 1997. His name did accidentally crop up in relation to Cuba at least once after a memorandum dated March 17, 1986, was not properly redacted in relation to a court filing. The classified memo read: ''I would like to propose you meet with Tom Hewitt, who successfully established an intel network in Cuba.''

"The document did not identify the country or agency Mr. Hewitt worked for," the New York Times reported in 1989, noting that the censored version of the sentence was supposed to read: ''I would like to propose you meet with a C.I.A. official who successfully established an intel network in a Latin American country.''

After his death in 2004, Hewitt’s widow Millie, for her part, said she was stunned to learn that her husband was being honored posthumously with the Distinguished Intelligence Medal, the CIA’s highest award, for his role in the Cuban missile crisis. Part of the citation reads:

“Public credit for the discovery of the missiles in Cuba was given to the U-2 reconnaissance aircraft in order to preserve the security of the team that Mr. Hewitt created, trained, managed, and motivated through one of the darkest periods of the Cold War. … It was his commitment to the mission, dedication, and obligation to the agents he ran in Cuba that resulted in the collection of intelligence that impacted on the course of history.”

While Naylor’s revelations fill in some crucial details to the Cuban missile crisis story, other historians in recent years have called for a complete overhaul of the entire narrative. While the story is often cast as an act of aggression by the Soviets, at the time of the crisis the U.S. had nine times the number of nuclear warheads as the Soviets and a much more reliable delivery system. There were also missile installations in Turkey, Italy and Great Britain capable of reaching western Russia, writes Benjamin Schwarz at The Atlantic, while the Soviets had only a handful of intercontinental ballistic missiles that could reach the mainland of the U.S. In the face of that overwhelming firepower, the Soviets felt a need to try and even the score by placing warheads in Cuba, leading to the crisis. The Soviets would not reach nuclear parity with the U.S. until the early 1970s, and would not possess more warheads than the U.S. until 1976.