When he posed for this underwater holiday snap, the diver in the foreground thought he would merely have a souvenir for the family album.
In fact, it is a key piece of evidence in a deep-sea murder mystery.
Ringed on the right is the body of honeymooner Tina Watson, who police believe was killed while diving by the man she had just married.
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The body (ringed): The tourist spotted it only after the picture was developed
And on the left is a diving instructor swimming desperately towards her in the hope of saving her life.
The unidentified tourist and his friend who took the picture did not realise the drama they had captured with their underwater camera.
It was only after the picture was processed and they learned of 26-year-old Mrs Watson's death that they realised they had "frozen" a possible crime scene.
Gabe Watson and his bride had travelled from their home in Hoover, Alabama; to Australia for their honeymoon.
Ten days later she died 80ft below the surface of Queensland's Coral Sea after diving down to a wrecked boat off the city of Townsville.
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Death at sea: Tina Watson died while diving on honeymoon
Mr Watson, a certified rescue diver, raised the alarm when he surfaced, saying his wife had got into difficulty in strong currents and had panicked.
Police have expressed concerns about his account of the incident in 2003 and have been investigating ever since.
Mr Watson has not been charged in connection with his wife's death and will give evidence to the inquest in Townsville through a video link from the U.S.
He has claimed hundreds of thousands of pounds compensation from a travel insurance company for the "mental anguish" he says he suffered after witnessing his wife's death.
But U.S. police have sent a warning e-mail to insurers officially naming him as a murder suspect.
When the FBI and two Queensland detectives raided his home in April this year, they seized his computer and other material.
Detective Gary Campbell told coroner David Glasgow that there were "issues of concern" to investigating officers, which included the supposed malfunction of Mr Watson's dive computer.
He had given several differing reasons why he could not rescue his wife, all of which were contradictory with his qualifications as a rescue diver.
Police had also noted Mr Watson's "slow" rate of ascent when going for help, and his statement that he had tried to communicate his distress to other divers under water, including grabbing and shaking one of them - a claim not borne out by any of the many divers interviewed, including, it is believed, the one in this photo.
There was also a claim - denied by Mr Watson - that he asked Tina days before their wedding to change her work insurance policy to make him the beneficiary.
The inquest is expected to last for a fortnight and if the coroner delivers a verdict of "foul play", charges could follow.
Newleyweds: Tina and her husband Gabe, a rescue diver
Horrific picture of drowned diver captured in underwater tourist snap | the Daily Mail