The jury in the case of wealthy Hertfordshire farmer William Taylor have found his estranged wife Angela Taylor and her lover Paul Cannon guilty of murder and arson.
Angela Taylor and her partner Paul Cannon had a "venomous hatred" for 69-year-old Bill Taylor because he would not agree to divorcing her.
WhatsApp messages found on Cannon's phone revealed a plot to kill Mr Taylor, a multi-millionaire who owned farms and land near Hitchin in Hertfordshire.
A selection of the lurid coversations were played to the jury of eight women and four men at St Albans Crown court.
Cannon and Angela Taylor who sent 28,000 messages to each other over 148 days, believed their WhatsApp messages were safe, secure and could not be read.
Cannon had deleted them, but a police officer found them stored on the iPhone 6's memory.
On 4 November, after the jury had brought in the verdicts, Judge Michael Kay QC told the couple he would sentence them on 8 November.
Before they were led from the dock he told the couple: “There is only one sentence that can be passed and it will be a life sentence”.
At the sentencing, the judge will determine the length of time each must spend behind bars before they can be considered for parole.
The jury heard that Mr Taylor disappeared shortly before his 70th birthday on either 3 June or 4 June from his remote farmhouse home called Harkness Hall on the outskirts of the village of Gosmore near Hitchin.
His body was found eight months later in mud on the bank of the River Hiz near Hitchin on 10 February last year by fisherman Eric Jackson.
It was just over 2 miles north of Harkness Hall and close to Angela Taylor's home at Mill Farm.
By the body was a bottle of Baileys liqueur, a tea cup from Harkness Hall, the remnants of a corn on the cob and a plastic bag that related to Bill's tinnitus clinic.
Angela Taylor of Charlton Road, Charlton, near Hitchin and Paul Cannon of Pirton Road, Hitchin had denied murdering her husband.
A co-defendant, Gwyn Griffiths, 60, of Lucy Avenue, Folkestone who was a work colleague of Cannon was cleared of murder on the direction of the judge during the trial.
All three defendants denied an alternative, lesser charge of conspiracy to murder between 12th February and 5 June.
Mr Griffiths was found not guilty and discharged.
William and Angela Taylor had been in a relationship since 1992 or 1993. They had married in November 1997 and had three children.