The 48-year-old PC was identified as the prime suspect after Ms Everard went missing on March 3, and he was questioned by police the day before her body was finally discovered.
Instead of confessing to the horrific crime, Couzens told a string of lies to investigators in order to shift blame away from himself.
The court was told earlier in the proceedings that Couzens was questioned at his home in Deal, Kent, in an emergency procedure by officers urgently trying to find Ms Everard.
The PC said he did not recognise Ms Everard but “disclosed that he had financial difficulties and he and his family were being threatened by a gang of Eastern Europeans”.
“He said that two or three weeks ago he had underpaid a prostitute (he usually meets them at Hotel Bursten or the Holiday Inn in Folkestone) and a gang with links to this prostitute told him that, as a consequence, he had to deliver them ‘another girl’,” the case summary revealed.
“They said that if he didn’t, they would harm his family. He also detailed that that the gang had been watching him at his house.”
Couzens “said he kidnapped Sarah Everard and drove her out of London. When he got between Ashford and Maidstone, he was flashed by a Mercedes Van with Romanian number plates”.
“He pulled into a layby and three Eastern European men got out of the van and took Sarah Everard.”
Couzens told police she was “alive and uninjured” at the handover, between 11pm and 11.30pm on March 3, and he offered a description of the Eastern European men.
But at the Old Bailey on Friday, Lord Justice Fulford confirmed this account was “entirely false”.
The moments before the kidnapping were captured on CCTV. Two figures could be seen on the edge of the South Circular next to Couzen’s hired car which had its hazard lights flashing.
The vehicle, hired by Couzens on February 28 in Dover, was later tracked leaving London and driving to the Tilmanstone area of Kent.
He returned the car to Enterprise hire on March 4, the morning after the kidnapping, having transferred Ms Everard to his own vehicle.
Ms Everard’s body was discovered on the afternoon of March 10, in an area of woodland around 100m from land which Couzens and his wife bought in Ashford in 2019.
Her body was in a large green builders’ bag and had been dumped in a stream, the court heard. She was later identified by her dental records.
Police investigations discovered that Couzens had bought self-adhesive film on February 28 and a tarpaulin and bungee cargo net on March 6 through Amazon, as well as two green rubble bags purchased from B&Q on March 5.
Couzens wiped the data from his phone on March 9. He was questioned on March 11 and 12, and replied ‘no comment’ to all questions.
Carolyn Oakley, CPS Specialist Prosecutor in the Special Crime Division, said : “Today Wayne Couzens pleaded guilty to the murder of Sarah Everard. This plea is as a result of a great deal of hard work by the prosecution team. The police should be commended for their thorough and tireless investigation into Sarah’s disappearance.
“Wayne Couzens lied to the police when he was arrested and to date, he has refused to comment. We still do not know what drove him to commit this appalling crime against a stranger.
“Today is not the day for hearing the facts about what happened to Sarah. Today is a day to remember Sarah and our thoughts remain with her family and friends.”