On Tuesday 12 January, Wismond Exantus was at work in the ground-floor shop of the four-storey Napoli Inn in Port-au-Prince. At 4.53pm, when the magnitude 7.0 quake hit, the 24-year-old cashier had the presence of mind to squirrel himself under a desk as the building tumbled down around him.

By Saturday, 11 days later and hours after the government declared search and rescue operations to be officially over, he was pulled alive from the ­rubble. The story of Exantus – the last known survivor to emerge from Haiti's shattered ruins – is a remarkable tale of crisps, beer, whisky, Twitter, a riot and a diminutive Scottish woman rescuer.

As he lay in the wreckage of the hotel, a drama unfolded of chaos, screaming and, eventually, helicopters and help. Wedged into a tiny black cavity, Exantus knew nothing of what was happening outside. "He didn't know if it was night or day," said his brother, Enso.

He held his mobile phone throughout, but it was not charged, a torment which can only be imagined. With his other hand he groped around for supplies that had been scattered around the ruined shop: crisps, sweets, soft drinks and beer. When he wanted to sleep, he took a deep draught of whisky. "By the end he had drunk a whole bottle of White Label," said Enso.

The cashier dreamed, among other things, that he was in the middle of the ocean and riding a horse.

By Friday, after Exantus had spent 10 days in his dark tomb, the government declared the end of search and rescue operations. The chance of finding more survivors was negligible. International rescue teams started flying home.

By Saturday scavengers were picking over the wrecked hotel when they heard a faint tapping sound, barely audible, but insistent. They alerted a passing Greek TV crew whose local fixer posted the news on Twitter while the journalists phoned the Hellenic Rescue Service, a volunteer team which, much delayed and supposedly too late, had arrived in Port-au-Prince just the night before.

The team jumped into a borrowed car and raced downtown. "Within 10 minutes we were communicating with the man," said Apostolos Dedas, the team leader.

The Greek rescuers lacked the heavy equipment necessary to move the debris so a group of French ­colleagues at the airport preparing to fly out were scrambled to the scene with their machines. Four hours later they had cleared a tight space in the rubble, but the male ­rescuers were too big to fit down it to cut away the final debris.

"They needed someone else to go in but none of them was small enough," said Carmen Michalska, a 5ft 5in native of Kirkcaldy and Fife attached to the Greek team. "So I said I'll go and I went straight in." At the bottom she found Exantus alive and smiling. "He was just so happy to see us."

When Exantus and his rescuers emerged a waiting crowd of Haitians applauded and cheered. Michalska, 36, on her first mission with the team, wore a layer of grime and a big smile. She embraced colleagues, some teary-eyed. "This is my first day with the Hellenic Rescue Service and at this rate it won't be my last." Did she ever suffer claustrophobia? She laughed. "No. Good job."

Exantus was given oxygen, put on a drip and ferried to the French field ­hospital. Staff said he was tired, ­dehydrated and had abrasions on his arm but was otherwise fine. Asked whether chugging beer and whisky was ­advisable when trapped under rubble Gilles Gueney, a paramedic, shrugged. "Well, he's here."

Before slipping into a deep sleep, Exantus said he had been saved by divine deliverance. "Every night I thought about the revelation that I would survive. It was God who was tucking me away in his arms. It gave me strength."

• This article was amended on Monday 25 January 2010 to correct the spelling of Kirkcaldy.