When Gemma Spofforth takes to the blocks at the Aquatics Centre on July 29, it will mark the beginning of the final chapter of an extraordinary journey marked by the highs of victory and the lows of despair.
So extreme was her despair at times the Shoreham-born woman contemplated suicide, pulled back and forth by the voices in her head.
Swimming, in which she had excelled since a child, was something she considered quitting on occasions, especially following the World Championships in Shanghai last year where she went in as defending 100 metres backstroke champion but then failed to make it through the heats.
Spofforth returned to Florida, where she had moved to study in late 2006, and continued her voluntary counselling work at a crisis centre, both on the telephone and in person for those also in despair.
At Christmas, the 24-year-old was still unsure of whether she would attempt to qualify for the Great Britain team, such was the "insane pressure". Even in the lead-up to the Olympic trials, Spofforth emotionally detached herself in an attempt at self-protection.
She said: "I definitely felt numb going into it. I took away all the emotions that I might need to help me swim fast. I took away all the emotions that might give me nerves before the race.
"So I was just numb because I didn't want to be in the position where if I didn't make it I would be in the depths of despair. I didn't want to be trying to pull myself out of a hole. I needed to know that I could numb myself."
Through a huge effort of will, Spofforth qualified for the 100m backstroke in London, where she will look to go one better than her fourth place four years ago in Beijing. For Spofforth, the trials were akin to an epiphany.
"Coming off 2008 and everything that had happened to me it was almost like the end of an era, the final chapter," she said.
"At the meet I was really nervous so it was really nice to finish that off. That's when it was real, before the meet it never felt that real."