Malcolm Anderson (54) had even slept with his wife Anita that evening shortly before he and an alleged “hitman” brutally killed her.

Later that day Anderson took lover Claire Jackson (26) to the Christmas party before spending the night with her in a hotel.

The jury heard how he was so desperate to be with her that he plotted with John Height (38) to “get rid” of his wife.

Anderson, of The Mill, Kirton, Lincolnshire, admits murdering her on December 8 last year. But Height, of Driffield Way, Peterborough, denies the charge.

Anderson was UK operations manager at the Norfolkline haulage depot in Whittlesey, where Miss Jackson worked as an administrator.

Mrs Anderson split from her husband after finding out about the relationship. Anderson told Miss Jackson he would be getting a divorce and starting a new life with her, but was later reconciled with his wife.

Nottingham Crown Court heard that in November last year the lovers rekindled their affair during a work seminar involving an overnight hotel stay.

Anderson allegedly discussed his dilemma with Height, a mechanic, who agreed to help kill his wife in exchange for £20,000.

On the day she died, Mrs Anderson went to Nottingham with her daughter and bought a dress to wear at the Christmas party the next day.

But that evening, after the couple had slept together, Anderson allegedly contacted Height to tell him: “Ready when you are.”

He then immediately picked up a saucepan and struck his wife twice over the head before helping her into her car, the jury heard.

She was repeatedly hit with a hammer and stabbed before being thrown into the River Welland.

The next day Anderson and Miss Jackson also drove to Nottingham on a shopping trip before going to their work’s Christmas party and then spending the night in a hotel.

But the day after the party, Anderson fled to the Continent “panic-stricken” before deciding to return to the UK and giving himself up to police.

His wife's body was later found in the water near Deeping St James, by a fisherman. She was wedged under a tractor tyre.

A post mortem revealed her head had multiple fractures, she had been stabbed “many times” and her neck had been cut on both sides.

Height denies murder. The trial continues on Monday.