Toronto police believe there must have been some kind of "hugely insignificant" event that led to the murders of two midtown men Oliver Martin and Dylan Ellis nearly one year ago.

They also believe someone in the community knows something and isn't talking.

Det. Sgt. Gary Giroux told reporters Wednesday morning that police are still trying to determine the motive behind the murder and that they no longer believe the men were shot on June 13, 2008 in a case of mistaken identity.

Further forensic testing showed the gunman was standing between 18 to 24 inches from the vehicle when he shot two bullets inside the SUV, killing both men instantly.

Martin and Ellis were best friends who were both 25 when they died, had left their friend's apartment on Niagara Street, near Queen and Bathurst Streets, just minutes before they were shot to death.

The men left the party in Ellis' SUV with Martin's girlfriend but returned minutes later when they realized they still had their friend's keys.

The wheels had "barely stopped" in front of the friend's apartment when Ellis turned around to greet someone who had walked up to the vehicle, Giroux said.

"He said something to the effect of 'How's it going,' and then shots were fired into the SUV," he said.

Martin,who was sitting in the passenger's seat, yelled at his girlfriend in the backseat to "get down." A few seconds later, the shooter moved to the front of the car and shot a bullet through the windshield at Martin's chest, killing him.

It's not clear if the shooter knew the girlfriend was in the backseat, Giroux said.

It was a warm spring night when the men were killed and authorities say there were several people milling about the Queen West neighbourhood when the murder took place.

No one has come forward with information.

The detective said something must have happened between the time the men got into their car and when they returned to Niagara Street a few minutes later.

"No one in the world knew they were returning the keys," Giroux said.

"It might have been a hugely insignificant event but it was important enough to the offender," he said. "(An event that is) not important in the minds of his family or the girlfriend in the backseat but significant enough to the offender for him to pull out a firearm in a public place and start shooting."

The detective said he's confident there are people in the neighbourhood who saw something but are hesitant to come forward because of their own personal reasons.

Early in the investigation, police believed they were looking for a suspect described as a young black man on a bicycle. On Tuesday, Giroux said investigators are no longer certain how that person fits into the story's narrative.

Investigators are hoping to spark renewed interest in the case with the upcoming anniversary. On Wednesday, police released a new picture of the men, renewed their reward offer of $50,000 and announced a poster campaign.

Police released the new picture -- snapped by Martin's girlfriend just three minutes before the men were murdered -- in hopes of evoking an emotional response from the public and to elicit more tips.

The picture shows the two friends laughing together in an unguarded moment. Martin's girlfriend hesitated to release the picture to the public because it was taken in the last minutes she shared with her love, Giroux said.

Police will not release the highly emotional 911 tape, he said, which recorded the initial phone call the girlfriend placed to police minutes after the murder.

"The phone call increases in intensity when she realizes she's alone and in the dark," he said.

Police have dissected the men's past, hoping to find some clues that would lead them to a possible suspect. However, Giroux said there was no evidence to suggest the men had led anything but decent, crime-free lives.

Starting Wednesday, police are launching a media blitz which will see the men's picture postered all over the Queen West neighbourhood and on subway platforms.