A three-man assassination squad scouted out Dublin crime boss Robbie Lawlor's movements before carrying out his contract killing in Belfast, a court heard yesterday.
They formed a cell intercepted by police following the shooting but then released and allowed to leave Northern Ireland, it was alleged.
The claims were made as bail was refused to another man charged with the murder of Lawlor in April 2020.
Counsel for Adrian Holland (39) claimed he is an innocent "mug" in a plot which involved a €50,000 cash payment being made to members of the Limerick-based McCarthy-Dundon gang for services rendered in luring Lawlor to his death.
Joe Brolly contended: "I smell a rat in this case, I've smelt a rat from the outset."
Lawlor (36) was shot dead outside Holland's home at Etna Drive in the Ardoyne area of north Belfast.
A gunman emerged from the house and opened fire in broad daylight.
Originally from Dublin, Lawlor had been heavily involved in a violent feud between rival Drogheda-based factions.
Previous courts were told he may have travelled to Northern Ireland because he feared he was going to be attacked.
But his killing had already been commissioned three weeks earlier at a meeting in a Sligo hotel attended by an international drugs dealer, it has
been alleged.
Neither Holland nor 47-year-old co-defendant Patrick Teer, of Thornberry Hill in Belfast, are suspected of carrying out the shooting.
Instead, they remain in custody charged as part of a joint enterprise to murder, based on their alleged involvement in its preparation.
Belfast Magistrates' Court heard yesterday that Lawlor is believed to have shot and paralysed a boss in the Drogheda-based Maguire gang, and also carried out the gruesome murder of teenager Cian Mulready-Woods.
That feud was said to have formed the backdrop to his eventual killing.
A three-man cell, including the gunman and getaway driver, allegedly operated in Belfast from at least the day before Lawlor was shot dead, working on the planning, execution and aftermath.
Based on CCTV footage, those movements included a meeting at Tesco car park and "scouting out" an address at University Road where the victim had been staying, according to Mr Brolly.
He said the trio were arrested as they left Belfast after the shooting, taken for questioning but then released.
"The three people believed to be the assassination team have been allowed to leave the jurisdiction, they have never been subject to any follow-up investigation, and they have been airbrushed from the papers," counsel claimed.
The court also heard two women believed to be linked to the McCarthy-Dundon gang were allegedly caught red-handed with a suspected €50,000 "blood money" payment near Portlaoise following the shooting.
With Holland denying any role in the murder plot, Mr Brolly questioned why he would get involved in an attack at his own home and then remain there in the aftermath.
"There's a fundamental flaw at the heart of this investigation," the barrister submitted.
Denying bail, however, District Judge Alana McSorley ruled: "I'm not satisfied any bail conditions could mitigate the risks in this case."