Two family members said in separate interviews that the men may have been set up by the middleman, who offered them an assignment to sail a fishing boat from the Southeast Asian country to mainland China. The four – three of whom were experienced fishermen – were told that the vessel had been impounded for fishing violations two years earlier, but was about to be released.

Well before the men were convicted, their families had informed the city’s police of Big Snake Nam’s role. But they have yet to hear from the force and are renewing their call now that the four face the prospect of a life behind bars.

The families also revealed that when the four arrived in the Philippines, a mysterious Chinese-speaking man picked them up and paid for all of their expenses for eight days until they were arrested during a police raid on board the boat. The four did not even have to present their passports when they checked in at hotels.

Their family members suspect that the middleman avoided them having to do so, to prevent the four leaving any clues to their whereabouts while in the Philippines.

“I hope (the middlemen) can come out and tell us the truth, to tell us the real purpose of the trip and to show that the four of them were all innocent,” said Winkey Leung Wing-lam, Leung’s 19-year-old daughter.

Lo’s sister, Lo Shu-ho, said: “If we are able to track down the middlemen, and if they are willing to talk about the incident, then the judge would have more to consider in the appeal.”

Big Snake Nam was identified as “Snake Nan” in the court judgment. His full name is Kwok Keng-nam, according to the convicted men’s families.

Back in 2016, when the middleman approached Leung to retrieve the fishing boat – which he said was owned by his brother-in-law Wong Sun-foon – he paid him HK$15,000 (US$1,915) up front in Hong Kong. He promised another HK$15,000 after the job was done. The two had known each other casually before then.

Leung then enlisted his friend Lo to join the mission.

The third convicted Hongkonger, Chan, met “Big Snake Nam” through a man called “Brother Man”, or “Man Gor”, as identified in the court judgment. Chan had befriended “Man Gor” in a video game arcade in Tsz Wan Shan, Lo’s sister said.

She added that the middleman had also tried to rope in a fifth person, who turned him down. The families tracked down this fifth person, who gave them Big Snake Nam’s phone numbers. But the lines had all been disconnected.

Lo Shu-ho said she had heard, from people claiming to know “Big Snake Nam”, that he was in the business of buying and selling boats.

“I heard that he used to play mahjong in Cheung Chau sometimes. But he has since disappeared,” she said.

Both Leung and Lo were Cheung Chau residents who used to be fishermen. Kwok also used to be a fisherman, while Chan was a renovation worker.

Winkey Leung said her father initially rejected the job because he felt the Philippines was too far away. She had also tried talking her father out of it.

“But later on he said [Big Snake Nam] really could not find enough people to do it. He had agreed to take the job, and so he was going to do it. I told him to be careful,” she said.

The four arrived in Manila on July 4, 2016. It was a man who called himself “Tung Gor” or “Brother Tung” – but never gave them his full name – who met them and arranged and paid for their accommodation and meals.

“My father told me at the time that he did not have to present his passport when he checked in at the hotel. Someone did so for them. The person even took them around for food and fun,” Winkey recalled.

The four waited in Manila for several days without knowing when they could board the boat. At one point, a worried Leung told his daughter that he wanted to return to Hong Kong.

This was after they had been driven four to five hours to Subic Bay. Leung told his daughter he found the place “windy”, “stormy” and “scary”. The four told the middleman that they wanted to leave. It was then that they were promised another HK$10,000 if they chose to stay. They agreed.

On the eighth day of their visit, they boarded the boat without incident. But just hours later, to their utter shock, then Philippine police chief Ronald dela Rosa led a team, together with reporters, to board the boat and had them arrested.

Officers took out everything inside the four men’s bags but could not find any drugs, according to video footage presented to the court. The men were then taken briefly to a room with no light. When they were escorted out, police asked them to open their bags again. There was a brown bag containing drugs in Leung’s bag. He told his daughter that he had not seen the bag before.

That was when their worlds fell apart.

Winkey and Lo Shu-ho said they knew very little about “Big Snake Nam”, his brother-in-law Wong Sun-foon and “Man Gor”. Sister Lo feared that the middleman had already fled to mainland China.

Asked by the Post if police had tried to help the families, a spokesman said the force had no comment.

The four men’s families had a difficult time finding lawyers to take on the case because many were not willing to represent suspected drug offenders.

The Philippines’ firebrand president, Rodrigo Duterte, launched a war on drugs when he came to power in 2016. Thousands of suspected drug offenders were believed to been executed in extrajudicial killings before due legal process could take place.

Mystery loomed in the four men’s trial earlier this year, when the previous judge who handled the case said he had received death threats. Another judge was then assigned to take over after 15 court sessions had already taken place.

Over the past two years, Lo’s sister has visited the Philippines about 20 times to visit her brother. Winkey Leung visited the country about 10 times.

The four were detained in Subic Bay prison before they were moved to the maximum-security New Bilibid Prison.

While at Subic Bay prison, the four were confined to a cell so small that they “did not even have space to stretch”, Lo Shu-ho said. A six-foot bed was shared by six people. Many others slept on the floor. Some had to sleep by the sink.

Whenever she visited her brother, she said, they would chat for up to six hours at the prison playground. It broke her heart, she said, having to leave her brother behind each time visiting hours were up.

The case has brought the four families together. They took turns to fly to the Philippines to visit the four and bring them daily necessities like medicine and soap.

In her judgment, presiding judge Roline Ginez-Jabalde ruled that the video of the raid on the boat was a compilation of “selected portions” by Philippine journalists, with “gaps between segments”. The judge also charged that the four Hong Kong men had failed to mention what happened to the original crew that manned the boat to the Philippines.

On this, Democratic Party lawmaker James To Kun-sun, who has been assisting the four, argued that it was “too much” for the judge to ask the defence to prove who planted the evidence, as the Philippine journalists could not state with certainty whether the drugs had been placed in the bag by police.

Lo’s sister said it was not surprising that the four men did not know the original crew, as the trip was arranged through middlemen.

To help cover the legal fees, Winkey Leung has decided not to pursue further studies and is now working in customer services at a bank.

The last time she saw her father was when she was in the Philippines for the court judgment. She broke down when the judge delivered the ruling.

“I believe that my father is innocent. When I was young, he told me never to get my hands on drugs. He once told me, ‘If you see drug users in the park or somewhere else, you must stay away from them’,” she said.

The family has spent HK$1 million on legal fees so far. They have launched a crowdfunding campaign and hope to raise HK$3 million.