Mamdouh Habib went to Pakistan in 2001, on a journey that would change his whole life.
Mr Habib has never been formally charged
Mr Habib went, according to his wife, because he was thinking about resettling in Pakistan and wanted to look at schools for his children.
Instead he was hauled off a bus, detained in Pakistan, Egypt and Afghanistan, before being flown to the US prison camp at Guantanamo.
During nearly three years of detention there, he was accused by the US - though never charged - of training militants and of having prior knowledge of the 11 September 2001 attacks.
But his supporters have consistently denied all these allegations, and say he was caught up in the wrong place at the wrong time.
His lawyer, Stephen Hopper, told an Australian current affairs programme last year: "I believe that Mr Habib was picked up in a general sweep in Pakistan in the lead-up to the war in Afghanistan. I believe that perhaps his documents weren't in proper order and he was taken in for further questioning. At this stage either Australian intelligence officials or the CIA got involved and life went downhill dramatically for Mr Habib at that stage."
Mr Habib was born in Egypt, but moved to Australia in 1980, where he did a variety of jobs - driving a taxi, running a cleaning business and, later, a coffee shop.
He married Maha, and the couple had four children.
A religious man, Mr Habib taught Islamic scripture at a local high school.
Friends told an ABC documentary that he took his faith seriously, but was not an extremist.
Born in Egypt, but has lived in Australia since 1980
Arrested in Pakistan after September 11 attacks
Flown to Egypt, where his lawyer says he was tortured
Transferred to Guantanamo Bay in May 2002
Released January 2005
According to Maha, 20 years after his arrival in Australia, his life there had turned sour and he was suffering from depression.
Part of the reason, Maha has said, was that Mr Habib felt discriminated against by the Australian authorities.
The Australian Security Intelligence Organisation (ASIO) had shown an interest in her husband, she said, ever since 1992 or 1993, following a trip they made to New York to visit Mr Habib's sisters.
Mr Habib also visited Sheik Omar Abdel Rahman, who was later sentenced to life imprisonment for attacking US targets, and was accused of being behind the 1993 World Trade Centre bombing.
Maha has told the Australian media that her husband did not support Sheikh Omar's actions, but simply wanted to try and raise money to buy him medication for diabetes.
"He was isolated and sick, you know - just for human rights. It was something to do with the human rights," she told ABC.
Mr Habib was also upset by the fatal shooting in the street of his son's best friend.
So in July 2001 he travelled to Pakistan to investigate opportunities there.
In October of that year, as he travelled on a bus to Karachi to catch his flight home, he was arrested by Pakistani police.
Although Mr Habib has never been formally charged, the Australian government has said the US believes he had prior knowledge of the 11 September 2001 attacks on the US, which had happened one month before his arrest.
The US has also alleged that Mr Habib spent time in Afghanistan and helped to train al-Qaeda militants, although, now the US has decided not to press charges, the precise allegations against Mr Habib may never be known.
In fact, ever since his arrest, it has not been clear what Mr Habib was being held for.
The former Pakistani Interior Minister, Makhdoom Syed Faisal Sawleh Hayat, told the Australian current affairs programme Dateline that Mr Habib was linked with the "terrorist element" operating at that time.
However, later in the same interview, he suggested that Mr Habib was assumed to be guilty just because he was in the restricted province of Baluchistan without proper visa documents.
Mr Hayat said that once the Pakistani authorities had finished interrogating Mr Habib, they handed him over to Egypt at the US' request.
Mr Habib was flown to Egypt at the end of 2001, or early in 2002.
There, Mr Habib has alleged, he was tortured.
"I was beaten, electric shock... no sleep, injections, brainwashed - unbelievable stuff," he told the BBC.
He said he was made to feel like a baby and forced into making a number of confessions. "I just repeated what they wanted me to say," he said.
Mr Habib was then transported to US custody in Afghanistan, and from there, in May 2002, to Guantanamo Bay in Cuba.
His letters home to his wife and four children pointed to the kind of treatment he is alleged to have received there.
"I've been blindfolded for eight months. I never see the sun, but I see you and the kids every minute. I never forget you or forget my children," he wrote.