Two Australian drug smugglers were transferred from Bali's Kerobokan prison on Wednesday (March 4) to a jail on Nusakambangan island in Central Java, a tell-tale sign that the leaders of the "Bali Nine" drug syndicate will soon be executed.

Myuran Sukumaran and Andrew Chan now await death by firing squad. We recap how the two friends, who dabbled with drugs since they were young, became ringleaders of the notorious syndicate.

Early Days

Sukumaran and Chan met in 2002 at a friend's place at a time when both were drifting into crime. They had attended the same high school in western Sydney but never crossed paths until that day.

Chan, now 31, had dabbled with drugs as a teenager, and was a self-confessed "black sheep" in his family of Cantonese-speaking migrants from China who have several restaurants in Sydney. Even though he lived at home and was working for a large catering company, he believed he "wasn't really going anywhere in life".

Sukumaran, now 34, was born in London to Sri Lankan parents who moved to Sydney when he was a young boy. He dropped out of university and was working in a mailroom, but was determined to strike it rich quick, no matter how. He turned to selling drugs after a university friend introduced him to a criminal world which offered the glitzy promise of fast cars, nightclubs and instant rewards.

Birth of a drug syndicate

Three years after they first met, Sukumaran and Chan teamed up to mastermind a plot to bring more than 8kg of heroin with a street value of A$4 million (S$4.25 million) into Australia from Bali. If they were working on behalf of someone else, they never revealed.

Their plot involved strapping drugs to the bodies of seven young couriers, who were provided with money and hotel accomodation.

The group, which later became infamous as the Bali Nine, included a woman, Renae Lawrence, then 27, and 18-year-old teenager Matthew Norman, and were paid as little as A$5,000 each.

Chan was the "godfather" of the ring, recruiting employees of the catering company where he worked, which included Norman, Si Yi Chen, now 29, and Martin Stephens, now 39. Renae later said she had been to Bali on previous drug runs for Chan who himself had previously worked as a courier. Three others were from Brisbane - Vietnamese-Australian Tan Duc Thanh Nguyen, window cleaner Matthew Czugaj and Scott Rush, who had drug problems himself but was planning to join the Australian military.

Sukumaran was the "enforcer" of the group. He was not known to Australian police despite his criminal record, and had never been arrested before he was nabbed in Bali.

Some couriers later claimed that Chan and Sukumaran threatened to hurt their families if they did not cooperate, though the duo denied the claim.

Crime and Arrest

By April 6, 2005, the group members landed in Bali and met Chan and Sukumaran at their hotel where they were split into separate groups and handed out temporary SIM cards to stay in touch.

Ten days later, the group met again for a final briefing, when they were given money to buy loose shirts and sandals, and advised not to wear clothes with any metal attachments to avoid tripping airport metal detectors. They had also been told to quit smoking for two weeks to not appear anxious when they alighted at Australia.

Unknown to them, the group was under constant surveillance after local police received a tip-off from their Australian counterparts, media reports said quoting prosecution evidence put forward in court. The Australians had provided information in great detail, including their pictures, passport numbers and duration of stay, along with a rejoinder that Indonesians should take whatever actions they deemed necessary when they saw the suspects.

The heroin was supplied to Chan by a Thai prostitute called Cherry Likit Bannakorn who went to Chan's hotel room with a bag full of packages. She has since slipped through the cracks and has absconded.

On April 17, as some couriers entered the airport with heroin packets strapped to their bodies, they were intercepted and arrested. Others, including Sukumaran, were found in their hotel rooms with heroin and strapping material and arrested, while Chan was off-loaded from his flight that evening. Police found a number of cellphones on him but no drugs.

Trial, sentencing and clemency

During sentencing in February 2006, Sukumaran and Chan were given the death penalty because they were found to have organised the operation and were accused of not showing remorse. The seven couriers are now in jail in Indonesia, facing sentences of between 20 years and life imprisonment.

After the verdicts, a long series of appeals began. Over time, the pair admitted to what they had done and expressed remorse and begged for forgiveness at a judicial review in 2010. They lost all appeals, including the final one challenging the denial of clemency by President Joko Widodo.

Chan and Sukumaran are now among a group of foreigners, including a Frenchman and a Brazilian, who are facing imminent execution. Australia, too, has been piling pressure on Indonesia to change course on the execution. Prime Minister Tony Abbott and Foreign Minister Julie Bishop repeatedly spoke to Mr Joko to persuade him to spare their lives.

The families of the pair have also been calling for Mr Joko to show mercy claiming the duo are reformed characters after years in prison.

The steadfast refusal of Indonesia to grant clemency has stirred deep anger in Australia, where a "boycott Bali" social media campaign is gaining momentum among travellers. However, there are others, themselves victims of drug abuse, who are lamenting how these criminals have been glorified as heroes.

Last days

On Wednesday, Chan and Sukumaran looked relaxed as the prison guards took them to the remote island where Indonesia carries out executions. The pair, reportedly, washed and got dressed in less than 10 minutes after they were told they were to be moved to Nusakambangan. After some administrative procedures, the Australians were handcuffed and taken to separate armoured vehicles each with 10 heavily armed police officers. Sukumaran took several pencils in a plastic bag, clothes, a Bible and a drawing book, Australian media reported.

Both condemned men will be informed at least 72 hours in advance of their execution, and granted three wishes before being put in isolation cells to await the final judgment.