Menachem Begin was Israel’s most reviled and misunderstood prime minister. Reviled by Britain for his paramilitary activities against the British Army in Palestine, Begin was a keen admirer of the Westminster parliamentary system and English common law. Reviled by Jimmy Carter as a hawk who refused to cede an inch of territory, this ultra-nationalist signed the peace treaty with Egypt that returned the Sinai. Reviled by the left as a racist and fascist, Israel’s first right-wing prime minister summoned the head of the Mossad soon after his victory and instructed him: ‘Bring me the Jews of Ethiopia.’

That unexpected order from a mercurial leader began a train of events that led to Operation Moses, the covert immigration to Israel of thousands of Ethiopian Jews, whom the Israeli Orthodox rabbinate had only latterly recognised as halachically Jewish. How they ended up in Ethiopia is the subject of legends, but no firm historical answer; yet while their adopted homeland referred to them as falasha (‘landless’), they knew themselves as ‘Beta Israel’ — ‘the house of Israel’. They had a land, Jerusalem, and would return one day. As an Ethiopian Jewish children’s song ran: ‘Stork! Stork! How is our country Jerusalem doing?’

The gap between that longing and its realisation over a series of months in 1984 and 1985 is the subject of Raffi Berg’s Red Sea Spies. Posing as European investors, Mossad agents purchased Arous, an abandoned Italian resort on the shores of the Red Sea, convincing Sudan that they could bring tourists back to the country. To that end, they flooded Europe with glossy brochures for a package holiday ‘a wonderful world apart’, with ‘some of the best, clearest water in the world’.

By day, they ran their diving resort; by night, they sneaked Jews out of the refugee camps in Sudan to which they had journeyed. Cut off from other Jews for millennia, Beta Israel believed themselves the last of the Israelites, and were astonished to learn that Jews could be Europeans.

Initially, the returnees were spirited through the desert back to a coastal point near Arous. There, special forces lay waiting with dinghies to row them to a naval ship moored out in the Red Sea, which in turn delivered them home to Israel. Discovery and death hung over these tense, danger-drenched night crawls; the dinghies eventually had to be abandoned after Sudanese troops mistook the convoys for smugglers one night and opened fire.

Mossad switched to airlifts, flying Beta Israel out from a disused British airstrip, although this only drew more attention, and the operatives found themselves in a series of close calls. In the end, Jerusalem paid off Khartoum and was allowed to transfer a further 6,000 Jews to Israel, provided they did so in secrecy, for the Sudanese president, Jaafar an-Nimeiry, feared a backlash from Arab allies.

To throw off suspicion, a commercial airliner was eventually used and Beta Israel flown to Ben Gurion via Belgium. Despite the spies’ best efforts, the mass immigration was picked up on, and when the story hit the press Khartoum cracked down, under pressure from the Arab world. In all, 8,000 Jews made it out and a further 14,000 were airlifted in 1991 in the follow-up Operation Solomon.

The scope of the operation was breathtakingly daring. As Berg writes:

What the Mossad mission amounted to was having to engineer a mass exodus of an unknown number of nationals of a foreign, hostile state, people who spoke no Hebrew, were antiquated in their ways, barely travelled and distrusted strangers.

Netflix’s Red Sea Diving Resort is an entertaining but licence-taking version of the same events, but Red Sea Spies is what really happened. There is none of the Hollywood colouring-in, and yet the book is all the more vivid for it. Berg knows he has a movie on his hands — part thriller, part dark comedy, all true — but instead of embellishing, he brings out the native drama in an improbable story of a clandestine homecoming, Exodus as orchestrated by a spy agency.

Berg, Middle East editor of the BBC News website, is not the first to tell this tale. One of the operatives, Gad Shimron, went public in 2007 with Mossad Exodus, a first-hand account of the perilous journey from Begin’s order to the airlifts. But Berg faithfully captures the perspective of Beta Israel, not least through Ferede Aklum, the teacher turned secret agent whose own attempt to reach Israel in 1973 was stymied by the Yom Kippur war, and who determined that all of Beta Israel should one day reach Zion.

Berg declines to speak as others do of a ‘rescue’. Beta Israel were not helpless victims. They walked in their thousands from the highlands of Ethiopia to the refugee camps of Sudan, many dying on the way, the rest facing death if they were uncovered as Jews. It was a risk they took to reach the shores of sought-after, dreamed-of, sung-about Zion and return at last to Jerusalem.