It took only 40 minutes from the time a whale cracked a hole in their 31-foot yacht until Maurice and Maralyn Bailey watched the vessel sink in the middle of the Pacific Ocean.

The yacht was their passage to a new life in New Zealand and their only home.

In the aftermath, the couple floated alone, together, on a 4-foot-long rubber raft attached to a 9-foot-long dingy, where they had escaped after the whale run-in. They had no motor, no radio and only limited provisions, including a few gallons of water and 33 tins of food.

Worse, because this was 1973, they had no prospects of anyone easily discovering their location or even knowing they were missing.

The harrowing story of the couple’s ordeal and eventual survival more than 50 years ago is being recounted in the new book A Marriage at Sea: A True Story of Love, Obsession, and Shipwreck by British journalist Sophie Elmhirst.

The book won the Gold Prize at the Nero Book Awards earlier this year and made Barack Obama’s summer reading list.

There’s no doubting that the Baileys were a quirky couple who dreamed of leaving their staid life in England for adventure and promise on the high seas. They got far more than that when a close encounter with a whale sank their yacht, the Auralyn, in March 1973.

Maurice’s choices placed them in even more jeopardy, including his decision to complete the voyage without bringing any communication devices that might have helped them be rescued sooner.

“Part of the escapist fantasy he’d always had was about getting away from other people, alone in the middle of the ocean,” Elmhirst tells PEOPLE. “What ends up happening exposes the folly of that fantasy.”

The couple spent 118 days — nearly four months — on their raft and dingy in the open water before they were rescued by chance by a passing Korean vessel.

Their experience made enduring international headlines. The Baileys wrote a book and toured extensively and told their story for the rest of their lives. Maralyn even appeared on the TV show To Tell the Truth.

Elmhirst’s new account is divided into three parts: before, during and after the yacht sinking that almost cost the couple their lives. She says she was drawn to understand what was motivating Maurice and Maralyn, who had decided to sell their home and go sailing across the world en route to New Zealand.

“I was interested in what it would be like to go through something like that as a couple, what effect it would have on the rest of your life,” Elmhirst says.

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The Baileys had sharply different personalities, with Maralyn being outgoing and optimistic compared to the socially awkward loner Maurice.

He appeared to be unlikely marriage material — much less wed an attractive, vivacious woman almost a decade younger than him. But Maralyn liked the fact that Maurice was unconventional, a sailor and daring in his own way.

Neither of them wanted to have children or be contained by social norms. She was eager to get out of her house and he did not have close ties with his family, including his parents, sister and two brothers, who all lived nearby.

Elmhirst admits that after all her research and speaking to friends and family of the couple, “I became very fond of Maurice.”

“He’s cantankerous, so it’s hard for him to be in company — but at the same time, he allowed her [Maralyn] to have a more adventuresome life and she could open up a life for him on a human level,” Elmhirst says. “She gave him warmth, support and confidence.”

The heart of the couple’s story, says Elmhirst, is that when the going got tough, Maurice was willing to let his wife be in charge. Despite being the more affable of the two, she did have a stubborn side.

Maralyn loved sailing yet never learned to swim. In an interview in March with the BBC, her half-sister Pat Brewin remembered once telling her, “What are you going to do if you got into difficulties or into the sea?’ She said, ‘I’ll be fine.’ “

“And she would, knowing Maralyn,” Brewin said. “She would find some way out of it.”

As for husband and wife choosing to go on a global boat trip without a key tool (a radio) or skill (her not being able to swim), Elmhirst tells PEOPLE “both cases were very conscious choices.”

“Maurice wanted isolation, he wanted to be cut off. That was part of the dream and the vision,” the author says. “Her not being able to swim was a defiance she had — ‘I don’t need to, I don’t want to and I’m not going to.’ ”

They had been married for nearly 10 years and were living a frugal yet comfortable life when in 1972 Maralyn convinced Maurice to sell their home, buy a boat and sail to New Zealand to start new lives.

As Elmhirst writes in the book, “Sailing tends to be full of people with money. Maurice and Maralyn were not those people. The boat took everything they had.”

The couple eventually set off in June 1972, with Maralyn then 31 and Maurice, 39, never imagining they would lose it all. The next spring, en route to New Zealand, she took a photo of their sinking yacht from the tented raft that would become their home for some 16 weeks.

“I have always put the credit down to Maralyn that she saved me,” Maurice said in an interview with the BBC broadcast in 2014. “She was the guiding light in everything we did.”

After their food had almost ran out, they made hooks from safety pins and caught fish, small sharks, seabirds and turtles to eat raw and used a tarp to trap and collect rainwater to drink.

After Day 100, they started making survival plans if one of them died, stranding the other.

“These included the possibility that one might have to eat the other’s body,” Maralyn said in a newspaper. “But we were both so emaciated that there were no edible parts except perhaps our stomach areas.”

Elmhirst says now that she was struck by the evolution of the couple when things went so very wrong. Maurice, who designated himself as the captain and last word on the boat, could not cope with the daily struggles of staying alive.

“He let go of any idea of him being a leader and she steps up,” Elmhirst says.

Brewin, Maurice’s sister, later told the BBC that “for every fish [Maralyn] caught, she used to save the eyes and call them Smarties [after the chocolate sweet] — so they had a ‘Smartie’ at night.”

After returning to dry land, the couple became vegetarians, Brewin added.

The Baileys had drifted almost 1,500 miles, into the dead of summer, when they were rescued by a South Korean fishing boat on June 30, 1973. At least seven other ships had passed the couple, never seeing them.

The Baileys returned to England, wrote their book about their experiences and bought another boat, Auralyn II.

They even went on a voyage to Patagonia with a small crew of friends who liked Maralyn and appeared to largely tolerate Maurice. (Some even returned home before reaching their final destination because Maurice made the trip intolerable, Elmhirst writes.)

After sifting through the offers from the British papers, they decided to sell their full account to The Daily Express for the considerable sum of £10,000 — or roughly $100,000 today — Elmhirst writes. (Paying for interviews is generally forbidden by news outlets in the U.S. but is widely accepted in the U.K.)

The Express sent journalists Ivor and Sally Davis to interview Maralyn and Maurice, and the four stayed in touch for the rest of their lives.

The couple eventually settled back into regular life and regular problems. Maralyn was diagnosed with cancer and died in 2002 at 61.

“Once she sadly passed, he reverts back to his earlier self,” Elmhirst says of Maurice.

Even as Maralyn’s cancer spread, she was still looking after her husband, trying to set up a marriage between him and a single acquaintance for when he became a widower.

The woman, however, declined the offer. Maurice lived a solitary life until his own death in December 2018. He was 85.

“Maurice drifted aimlessly after her death,” Ivor Davis tells PEOPLE. “I went to see him when he was on his own and he was a sad, sad fellow. She was the powerhouse in the relationship. She was the driving force. And he had lost his anchor.”