Vepkhvia Laliashivili, 53, who had worked for the Georgian ministry of internal affairs before moving to the UK in 2005, fatally stabbed Lithuanians Dainius Kulboka, 44, and Jonas Semenas, 45.
Shortly after midnight on January 10 last year, the victims were found dead in Mr Kulboka’s home in Tavistock Gardens in Ilford, east London, where all three had spent the evening drinking around eight bottles of spirits.
Prosecutor James Dawes QC had told the Old Bailey the evidence indicated that Laliashivili killed or incapacitated one man and then killed the other.
The defendant used knives he found at the house to inflict eight deep stab wounds to Mr Kulboka, and 52 stab injuries to Mr Semenas, some very deep, the court heard.
The prosecution asserted that sounds of the attack could be heard on a doorbell camera opposite the house, with one victim pleading for it to stop.
The motive was not known but it was claimed that the defendant owed the victims some £30,000 and may have killed them to avoid paying them back.
Laliashivili, from Plaistow, east London, who was formerly known as Vytautas Garmus, claimed he had no memory of events and was found guilty of two counts of murder.
Sentencing on Thursday, Mr Justice Wall said it was “pre-meditated” and “not an incident that arose out of a spontaneous fight”.
Jailing the defendant for life with a minimum term of 35 years, the senior judge said it was an “appalling act of violence”.
He said the defendant had summed it up himself while attempting to cast the blame onto someone else, telling jurors: “Whoever did this is not human – how is a human capable of doing this.
“A normal human being would not have done this.”
The judge said it was a “planned offence”, even though the evidence was not strong enough to sentence on the basis of murder for “gain”.
He highlighted the “brutal nature” of the attack; the defendant’s “determined” attempts to evade capture; and “the mental anguish that each man must have suffered over that 20 minutes of the incident as he became aware not only that he was going to die but that he would witness visibly or audibly the death of his childhood friend as well”.
Earlier, victim impact statements were read out in court as loved ones watched the sentencing by video link.
Mr Kulboka’s former wife Agnes Kulbokiene described him as a caring “family man”.
She said: “Our family lost Dainius and our hearts are completely broken.
“Not only ours, friends and close family going through this with us.
“He was the most caring person on this earth.
“He never turned his back on anyone, always there for anyone who needed a hand or support.”
Describing the effect on their teenage daughter, she said: “She talks about dad every day and still believes she will see him, waits for his call and will not delete any messages.”
Mr Semenas’ family said in their statement: “It takes only one second for fate to change one’s life.
“Our lives completely changed on January 10 2021.
“We learned about the death of a son, brother, uncle and a friend.
“We can’t believe that someone decided to take his life so cruelly….
“It seems we are not people from the same planet.”
The court heard Mr Semenas supported a project in Lithuania to fulfil the dreams of poor children at Christmas.
In mitigation, Mathew Sherratt QC said: “This was an all day drinking session that started at 11am and escalated into what was at the end of everything a savage, frenzied, double murder with all the hallmarks of rage and complete lack of any inhibition.”
However, he added that the defendant, a former police officer, did not have a history of violence and, given his age, was likely to die in jail.
Laliashivili became agitated as he was led from the dock to begin his life sentence.