A gangland feud led to the double murder of an underworld "Mr Big" and a mob "fixer" a court heard.
Paul Massey, 55, from Salford and his friend, John Kinsella, 53, from Liverpool, each had a "serious criminal history" and were "notorious" in the North West.
Both were gunned down in "stone cold murder" during a deadly feud involving rival crime gangs in Salford, Liverpool Crown Court heard.
Mark Fellows, 38, and Steven Boyle, 35, both deny the murders and the attempted murder of Wendy Owen, Kinsella's partner.
They sat in the dock, surrounded by six prison officers, listening intently as Paul Greaney QC gave the prosecution opening to the jury as the trial began.
Mr Greaney told the jury Massey was murdered in July 2015 and Kinsella almost three years later in May.
He said: "They were friends and associates. Moreover, each was well known, if not notorious, within the gangland of the North West, and both men undoubtedly had enemies.
"Their undoing has to do with events in the city of Salford, where serious violence broke out between two criminal gangs in 2015."
The first gang was headed by Michael Carroll, the jury heard, with Fellows and Boyle associated with that group.
The second rival gang was said to have been headed by Stephen Britton and called itself "the A Team".
Jurors heard Massey was associated with that gang and regarded by Britton as a mentor and in turn Kinsella was strongly associated with Massey.
At around 7.30pm on July 26, 2015, Massey parked his BMW outside his home in Clifton, Salford, and walked up the driveway.
A gunman lying in wait, followed him, firing an Uzi sub-machine gun and killing him before fleeing.
Police were unable to charge anyone until earlier this year when Kinsella was murdered.
At about 6.45am on May 5, Kinsella set out on his usual morning walk with Ms Owen and their dogs from their home in Rainhill, St Helens.
A man, allegedly Fellows, cycled up behind them on a mountain bike and blasted Kinsella twice in the back with a handgun.
He fell face down as Ms Owen "charged" at him but the gunman then turned the weapon on her, shooting, and she fled.
Fellows then calmly cycled nearer to Kinsella and shot him twice to the back of the head, the jury heard.
Mr Greaney said: "Unlike three years earlier, on this occasion, the killer was undone."
The jury heard CCTV evidence showed the gunman had cycled from the area of Fellows's home in Warrington.
Evidence suggested Boyle had acted as a "spotter" who positioned his Renault Clio so he could see Kinsella and Ms Owen approaching.
Mr Greaney said there were "clear parallels" that suggested the same killers carried out both murders.
Police investigating the Kinsella murder seized a Garmin Forerunner watch belonging to Fellows.
This type of watch worn by keen runners and cyclists has a GPS function enabling routes to be recorded, along with other information such as pace and distance.
Analysis by detectives showed a few months before the murder of Massey, the wearer of the watch had travelled from his home to the area behind a church in which the killer lay in wait for his victim on July 26 2015.
It showed, police say, Fellows on a "reconnaissance run" for the planned gangland hit.
Mr Greaney told the jury a painstaking review of CCTV systems was critical in the investigation and was to "unlock the case" as it showed Boyle and Fellows in the area at the time of the murder.
Ms Owen told police the gunman was slim and wearing a hi-vis jacket and black combat trousers but she was unable to clearly see his face because he was wearing a black snood and baseball cap.
Boyle and Fellows had made the same journey six days earlier, on April 29, only for Boyle to arrive too late to perform his role of spotter and the planned "assassination" was aborted on that occasion.
Their plan was thwarted by the simple fact Kinsella and Ms Owen had set off on their walk earlier than the killers had expected, Mr Greaney said.
Fellows told police the two men met there to arrange a drug deal.
The two spent 12 minutes together according to the CCTV footage, "discussing what had gone wrong with their plan to kill" Mr Greaney said.
At the time Fellows was working night shifts but was free to return to the murder plot six days later on May 5.
Fellows and Boyle set off on the same route much earlier that day to be in wait for their prey, the court heard.
The trial is expected to last up to six weeks.