From fighting in the playground to staging a series of armed robberies, his aggression led inexorably towards its terrifying culmination in a string of sex assaults. But what in his background led Imiela to rape so many women?
His childhood was violent. Imiela moved with his parents in 1961 from Lubeck in West Germany to Newton Aycliffe, County Durham. Here his Polish-born father would take out his frustrations on the young boy, beating him frequently.
At strict St John's Catholic school in nearby Bishop Auckland, Imiela was ridiculed for his distinct German accent - a severe handicap in the post-war North-East. All this led him to rely on his fists for protection, and as he grew older he developed into what his family called "a natural fighting machine".
When Toni - as his sister Jadwiga Imiela still calls him - was 15, his mother walked out and returned to Germany. "Mum could not cope," she says. "Toni was wild and became worse after she left. He was devastated. Every time he saw someone in the street who resembled her, his heart would sink. He thought she didn't love him."
Ms Imiela, 39, added: "Father withdrew to his pigeon loft and became aloof. Toni began playing truant, became a bit of a tearaway and would pick fights with other teenagers in the street.
Antoni Imiela's own son Aidan, 20, says: "My family always say it was as if he was designed to fight. He was incredibly quick with his fists and it took nothing to provoke him. He was well built, but agile with it."
In a series of letters he wrote to Aidan, Imiela showed no remorse for his crimes. And he confessed, "I cannot control my sexual urges", adding: "I'm a man, you must understand that sometimes you have no control over your impulses."
When Aidan told his father he was "mad", and had a wife who loved him, he replied: "You know what it's like when you're out with the lads and some girl is giving you the eye."
In his first letter to his son from jail, prisoner JR 4998 hinted at the truth. "I do not know how to say what should perhaps be said ... I felt proud when I saw in the papers the confidence that you put in me, and am so sorry that I have been charged with these crimes," he wrote.
He repeatedly says he is prepared to "do the time", and asks his son to look after his wife Christine.
To Aidan, the implications of the letters are clear. "Without saying as much, he is admitting things that he could not discuss openly. I am reconciled to his guilt," he said.
Imiela's early aggression led to ever more violent conflicts. While courting Allyson Pletts, Aidan's mother, he hospitalised a man he thought had tried to talk to her in a club.
Another time at the Iron Horse pub in his home town, he was charged with grievous bodily harm
after he "pummelled" five men he claimed threatened him.
While serving time for a series of post office raids, Imiela put a sign on the wall. Aidan recalled: "It said, 'Anybody who has a problem with me can come to my cell and have a go.' He was fearless. Nobody messed with him." During his relationship with Allyson, Imiela would often punch and kick her "simply because he was angry".
When she spoke to other men he would fly into a rage and beat her, only to calm down minutes later, apologise and shower her with gifts. Ms Pletts, 43, of Newton Aycliffe, said: "He was completely insecure and paranoid. He became possessive about me.
" If he thought I had spoken to another man it drove him mad. He would punch me and leave me bruised. I don't know why I didn't try to leave him. Perhaps it was because he was always so apologetic afterwards and would buy me presents."
It was after the birth of Aidan in 1983 that Ms Pletts discovered Imiela's dark side. In 1987, Imiela, wearing a balaclava and wielding a shotgun, held up a Darlington post office and escaped with £10,000.
Police raided the couple's home. He was forced to admit to his wife that whilst going out with her, he had committed numerous armed raids. Their relationship ended when Imiela went to ground for a year to avoid the police before finally giving himself up.
Ms Pletts said: "I knew he had been in Borstal at the age of 15 for armed robbery, but I didn't know he was still doing it. One day, whilst he was on the run, he leapt out at me from behind a bush as I was walking home. Another time he arrived at my friend's house pretending to be a salesman.
"He committed robberies because he craved a lavish lifestyle. We were comfortable, but he wanted more - the big house, a Ferrari and a flash lifestyle." But despite his violent nature, Ms Pletts said there was nothing unusual about their sex life, which was "actually boring".
Aidan is now adamant he never wants to see his father again. "I could live with being the son of an armed robber. He did not hurt anybody and was desperate for cash," he said.
"But these crimes are totally different. These women will suffer the rest of their lives. He has made our family's lives a misery, too."