London: It was one of the Mossad's most daring, complex and longest-running operations. But only now, 37 years on, is the story of a Red Sea diving resort run by the agency getting its moment in the sun.

"Operation Brothers," which ran for over three years in the early 1980s, was a breathtaking mission. At its heart was the Arous Holiday Village, a small beach resort billed as the "diving and desert recreation center of Sudaninfo-icon."

According to a brochure distributed to European travelinfo-icon agenciesinfo-icon, Arous offered a combination of desert vistas, sandy beaches and coral reefs, including real shipwrecks off the East African coast for diving enthusiasts to explore.

But here's what the brochure didn't say: It was all a front - devised and maintained by the Israeli intelligence agency, whose operatives would visit Sudanese refugee camps with trucks, load them up with Ethiopian Jews (also known as Beta Israelinfo-icon), embark on treacherous journeys across Sudan back to the resort, from where the Ethiopian Jews would be shipped or flown to Israel.

If this sounds like the stuff of a Hollywoodinfo-icon movie ... well, it now is. Decades after details about the story were first revealed, "Homeland" co-creator Gideon Raff has written and directed "Red Sea Diving Resort," inspired by the real-life events between 1981 and 1985. The movie, which is set to be released July 31st, was shot in South Africainfo-icon and Namibia last year and stars Chris Evans, Haley Bennett and Ben Kingsley.

No one has been more surprised at the renewed interest in the story than Gad Shimron, who played a key role in creating and running the Red Sea resort. Though parts of the story had trickled out in the Israeli mediainfo-icon over the years, Shimron's 1997 book, "Mossad Exodus; The Daring Undercover Rescue Of The Lost Jewish Tribe," was the first to detail the events at Arous.

"I'm very happy the story has been revived and brought back from the dead," Shimron tells Haaretz, noting he's "fairly sure" it was his book that inspired Raff to tell the story.

Shimron's book reads like a spy novel, complete with cliffhangers in which the protagonists escape thanks only to their quick wits. Shimron's career trajectory combining stints in the Mossad and years as a journalist made him the ideal person to tell the tale - or as much of it as the Israeli military censor and Mossad would allow him to recount.

"It was the experience of a lifetime," he reflects. "So much happened: We were shot at; I was arrested and interrogated by Sudanese security. Thank goodness nobody was killed or seriously wounded, but the operations moving the immigrants were definitely dangerous."

Very dangerous, in fact. Such as the time in March 1982 when the Israelis were fired upon by a Sudanese military unit that had followed them and their "human cargo" to the beach, believing they were smugglers. Shimron recounts that the ambush happened just as the agents were loading the last of a group of Ethiopians onto a rubber boat, sending it out to rendezvous with an Israeli naval vessel waiting in international waters.

As the shots flew over their heads, one of the Israelis started screaming at the Sudanese officer in charge. "What are you doing, you fool? Are you out of your mind shooting at tourists?" Threatening to complain to the Sudanese chief of staff, whom he mentioned by name, the agent continued, "Can't you see that we are organizing night diving here for tourists? We work for the Tourism Ministry, bringing tourists from all over the worldinfo-icon to acquaint them with the beauty of Sudan, and all you fools can do is fire at usinfo-icon?!"

The tactic worked and the officer stammered an apology. But the close call marked the end of the maritime rescue missions, which had taken place over the preceding six months. After that, from the summer of 1982 until the fall of 1984, small-scale airlifts took place. In all, there were 17 separate airlifts in which planes landed on a makeshift airfield in the desert and took off filled with Ethiopian Jews - all coordinated and executed by the Arous team.

But it wasn't all James Bond-esque escapades. Shimron admits that "in the long periods between the operations, we had the best time of our lives. Yes, we were living in very simple conditions, with electricity for only a few hours a day. But we lived in a paradise that had a beautiful view, fantastic beaches and diving sites - and we were being paid for it."

It begins with Begin

The story of Operation Brothers actually dated back to 1977 and the election of Prime Minister Menachem Begin. Reports came into Israel that Ethiopian Jews had started fleeing the civil warinfo-icon and famine in their homeland, many heading to neighboring Sudan where they were being housed in refugee camps. Although Sudan was a predominantly Musliminfo-icon state hostile to Israel, its geographical location made it a perfect pathway for Ethiopians hoping to continue on to the Jewish state. Begin summoned then-head of the Mossad, Yitzhak Hofi, to see what could be done.

But it was only four years later that the Mossad began scouting the Sudanese coastline, looking for locations where the Israel Navy could pick up groups of Ethiopian Jews and transport them to Israel.

It discovered a picturesque group of 15 empty beachside villas (complete with kitchen and dining room) that had been built by Italian entrepreneurs a decade earlier, in 1972. However, the site had been abandoned when the Sudanese authorities failed to provide the promised access road, and water and electricity.

Deciding that the deserted holiday village could be an ideal staging area from which to smuggle the Ethiopians to Israel by sea, the Mossad hatched its plan.

The Sudanese Tourist Corporation believed it was renting the resort - for the princely sum of $320,000 - to a Swiss company eager to create a new getaway destination. Of course, the company's "European" managers, diving instructors and windsurfing coaches were all actually Israeli intelligence operatives.

The Mossad leased the resort for three years and placed a handful of key agents there. They were charged with renovating it, hooking it up to the electricity and water, and turning it into a fully staffed, sun-and-fun tourist operation.

The local employees knew nothing of the resort's real goal, or the real identities of their bosses. And the guests who eventually stayed at the resort - making it such a success it even turned a profit - were also unaware of its true purpose. Save for one, as Shimron recounts in his book.

This guest, from Canadainfo-icon, caused panic when he took a diving instructor aside and stated, matter-of-factly and in Hebrew, that he knew the staff couldn't possibly be European. In fact, he was sure they were Israelis. The guest was Jewish and had previously volunteered at a kibbutz. He had watched the staffers prepare their breakfast every morning - and "only Israelis cut their salad vegetables so thin," he said. To the agent's relief, the guest kept the secret to himself.

The Sudanese staff might have similarly suspected something was odd about their employers' habits - such as teaching the staff how to bake sweet, braided bread each Friday for their special "Sabbath cake." The bosses would also disappear frequently and return exhausted when, using various excuses, they would be engaged in their true mission.

Humanitarian mission

Looking back, Shimron says Operation Brothers was a unique opportunity for the Mossad operatives, whose missions invariably involved bloodshed and conflictinfo-icon. Instead, in Sudan they got to play a key role in a humanitarian mission - one he believes is unique in the historyinfo-icon of intelligence operations.

Gad Shimron at Arous Holiday Village, pointing at a portrait of then-Sudanese President Gen. Gaafar Nimeiry in the early 1980s. Courtesy of Gad Shimron

As he writes in his memoir, "What other developed country would be ready to invest tens of millions of dollars to set up an operational infrastructure for secret activity in an enemy country, involving large armyinfo-icon forces, only to save several thousand famished refugees in civil war-torn Africainfo-icon?"

Filmmaker Raff approached Shimron three years ago to discuss formally optioning the book, Shimron says, but ultimately chose to create his own version of events using the accounts of other participants in the mission. It's a choice Shimron says left him "disappointed, but not bitter." And though he worries that the upcoming film "will be a Hollywood-style movie" that emphasizes American participation and won't accurately capture the covert actions, Shimron says he's still pleased this little-known story will be told to a global audience.

Shimron stresses it's important to remember that the bravest people in the story aren't the Mossad operatives, but those Ethiopian Jews who endured endless hardships trying to reach Israel by land, sea or air.

His book contains descriptions of these stoic, uncomplaining men, women and children who crowded into trucks, hid in wadis and climbed into small boats or planes with no idea where they were headed, but with utter trust in their rescuers.

"They are the real heroes of the stories, not us," Shimron tells Haaretz. "What they went through in order to fulfill their dream to come to Zion - no normal Israeli or any Westerner could have endured for even three days."

One possible reason Operation Brothers has been largely overlooked is that the total number of Ethiopians the operatives were able to send to Israel was relatively small over three years, compared to the more dramatic Operation Moses, which airlifted more than 7,000 Ethiopian Jews to Israel from Sudan (via Brussels) in less than three months, between November 21, 1984 and January 5, 1985.

But in Shimron's telling, the substantial amount of time, energy and money expended by the Mossad during Operation Brothers reflects the depth of Israel's commitment to bringing the Ethiopian Jews to Israel, and saving as many as possible from the famine, war and turmoil they were facing in Sudanese refugee camps.

Still, the success of Operation Moses was the beginning of the end for the Arous adventure. Shortly afterward, when Sudanese dictator Gen. Gaafar Nimeiry was toppled by a coup in April 1985, the remaining Israelis were evacuated from the resort and the holiday was over.

Keeping their distance

Though they had accompanied the Ethiopian Jews through their traumatic experience and admired them deeply, Shimron says security protocol dictated that the Mossad men keep their distance from their human cargo and hide their identities while transporting them to Arous. If caught, they needed the Ethiopians to maintain their cover stories, so they were told the people accompanying them were European emissaries, not Israelis.

It was only during visits to Israel, during breaks from their Sudan posting, that Shimron and his compatriots went to the absorption centers where the Ethiopian Jews were being housed. Even then, for security reasons they weren't able to openly identify themselves as their rescuers. As they spoke to the new immigrants in a mixture of Hebrew and Amharic, they identified themselves only as Jewish Agency workers.

But on one occasion, Shimron's cover was blown - by a small child.

Shimron writes that the kid came up to him in an absorption center and said in good Hebrew, "Uncle, I remember you from the red truck in the wadi!" Shimron admits, over 30 years on, that his own reaction surprised him. "I'm not a very sentimental guy, but I admit that a few tears were running down my cheeks."