Przemyslaw Golimowski was fatally stabbed and beaten with a golf club in front of Anna Swierczynska after he had stolen drugs and cash from 20-year-old Delpierro Mothersill.
Mothersill from Salcombe Close, Bedford; Taleb Hussain, 31, Park Road, Sparkhill Birmingham and Damien Rooney, 25, of Magpie Gardens, Wixams, Bedford were all convicted of murder by a jury majority of 11 to 1.
They were all sentenced to life with a minimum term of 26 years by Judge Richard Foster.
Jamil Jeng, 21, of The Close, Clapham was cleared of murder but convicted unanimously of manslaughter.
Philip Mendy, 23, of Russet Close, Bedford was cleared of murder, but convicted of manslaughter by a majority of 10 to 2. They were each jailed for 12 years.
During a six week trial, the six men and six women on the jury heard the Polish-born couple were in bed in the flat in St Mary's Street, Bedford early on Friday September 28 September last year when the revenge attack was carried out.
Ms Swierczynska told Luton crown court she had been woken at around 2am by the sound of “voices” in the kitchen and roused her 30-year-old boyfriend, who was sleeping beside her.
She jumped out of bed to get a bayonet that was on a wall. She removed it from its sheath, but one of the three warned her saying: "Are you sure you want to do this?"
Ms Swierczynska said it left her “terrified” and she dropped the knife to the floor.
One of the three, she said, had armed himself with a golf club that was already in the flat.
She said she found herself with the three in front of her and with her boyfriend behind her, but they got round her and reached past to attack him.
“They were beating him up and he was bleeding. All of them were having a go at him,” she told the jury.
Her boyfriend, who had the nickname Shevai, was struck by the golf club “more than once” and she also received a blow from it.
She said the three attackers all wore hoodies and two had track suit bottoms on while one wore “worn” jeans.
As the attack continued she said she tried to support her boyfriend by holding him up and keeping him on his feet.
Then he moved towards a window and was followed by the three who continued the attack.
She now had “route” for an escape and ran from the room, through the flat and out onto corridor where she called out for help.
Asked by prosecutor William Harbage QC what was happening to her boyfriend, she replied: “The men were by the window attacking him. He was bent over.”
Her boyfriend was trying to fight back using just his hands, but she said “They kept attacking him, they wouldn’t give up.”
She ran up a flight of stairs to the floor above, but couldn’t get anyone to help her.
Eventually she said she went back downstairs to her flat after the attackers had gone.
“There was blood all over, it was everywhere,” she said.
She said her boyfriend wasn’t in the flat and she went to a flat of his friend and found him there lying down.
“He was in a terrible state, blood was everywhere. I grabbed wet towels and put them on him to stop the bleeding and talking to him the whole time.
"He only said he was sorry the whole time,” she said.
An ambulance crew arrived, but Mr Golimowski was pronounced dead at the scene. He suffered 56 injuries.
At the start of the six-week trial Mr Harbage QC said that on the previous day, Mothersill - who is known as Del - had been attacked by Golimowski and another man at an address in Salisbury Street, Bedford.
"He (Mothersill) was beaten up, struck repeatedly with a pool cue and suffered cuts, bruises and a black right eye. He was robbed of money and drugs - heroin and crack cocaine," he said.
As a result a "mission of revenge" was launched by a furious Mothersill who the court heard was armed with a knife.
One stab wound went through Mr Golimowski's ribs into his heart, another into his liver and a third into his stomach. There was a fourth wound to his stomach.
As well as cuts and bruises, he had line marks on his back consistent with being struck by the golf club.
The prosecutor said the attack lasted for five minutes and no murder weapon has been recovered.
In a victim personal statement the victim's brother Andre Golimowski said that their mother was taken to hospital after learning of the death of her son. She died a week after Przemyslaw. He said: "We received a life sentence. Those responsible for his death are also responsible for the death of our mother."
Sentencing the men, Judge Foster said: "It is yet another example of toxic mix of drugs and knife crime in a town beset with such problems."
He said it was a "preplanned merciless revenge attack."
After the case, Detective Chief Inspector Adam Gallop said: "This was a ruthless and brutal attack, the likes of which have no place on the streets of Bedford.
"These five men broke into Przemsyslaw Golimowski's home with murderous intent, with seemingly no regard for the value of human life."