A "bunny boiler" love rival and her accomplice pal have been found guilty of murder after a businesswoman was tasered and stabbed to death in her home.
Sadie Hartley was found with more than 40 stab wounds lying in a pool of blood in the hallway of her home in Helmshore, Lancashire, on January 14.
Sarah Williams, 35, paralysed the 60-year-old with a 500,000 volt stun-gun before stabbing her to death with "demonic savagery".
Hartley and friend Katrina 'Kitt' Walsh, 56, were both found guilty of murder by a jury at Preston Crown Court today (Wednesday, August 17).
Sarah Williams was given a life sentence and ordered to serve a minimum of 30 years.
Walsh was also sentenced to life and ordered to serve a minimum of 25 years behind bars.
Williams had become "jealous and obsessive" over her victim's partner Ian Johnston, 57, after having sex with him a number of times before he resurrected his relationship with Miss Hartley.
But Mr Johnston and Williams continued to exchange naked photographs and sent a series of sex texts on December 3, 4 and 5 last year.
There were further similar exchanges between the pair after they met on Christmas Day, and again 10 days before the murder.
Williams, a ski travel firm sales advisor, sent Ms Hartley a spiteful letter saying she had been having 'unbelievably fantastic sex' with Mr Johnston but it failed to break them up.
Mr Johnston has denied he "led her on", telling the jury the relationship was "just sex" but Walsh told police Williams would "do anything" to be with Mr Johnston, even planting secret tracker devices on his car to follow his movements.
Williams - described as a 'bunny boiler' by friends - then enlisted horse riding instructor Walsh to help her execute the "perfect murder".
The jury was read extracts of a diary Walsh kept of the murder plot which were found at her workplace by police.
In September 2014, Ms Walsh wrote: "Sarah came round so got caught up in endless murder plots for Ian's other half."
Another diary entry read: "We're also seriously talking of getting rid of her opponent. I agree is probably a good play... she does seem to be a totally evil bitch."
The pair, both from Chester, travelled to Germany to buy the stun-gun last December.
CCTV showed the pair, both from Chester, boarding a Pride of Hull Ferry before travelling from Humberside to Rotterdam in Holland on December 9 last year.
As they prepared to drive to Germany, Walsh wrote in her diary: "I said no matter what her way of testing the bitch, then she could do with that zapper or she risks being injured herself.
"So will get a trip to Germany out of this. Took ages to wind down, all the excitement of plotting the perfect murder!"
Walsh purchased the murder weapon - a kitchen knife - at Tesco using her Tesco Clubcard.
Williams had previously texted her saying: “Don’t forget to crack on with your shopping…suddenly it’s time.”
As their plot neared its violent climax, the pair carried out a dry run at the £500,000 property by delivering flowers to Ms Hartley.
On January 7, the two women visited a Tesco store in Haslingden where Ms Williams bought a £3 bunch of chrysanthemums.
The aim of the 'macabre test run' was to double-check Ms Hartley lived at the address and see how she opened her front door.
Walsh delivered the flowers with Williams hidden from view nearby.
The next day, Ms Hartley emailed her business partner to say the episode was a "bit creepy" and "needless to say had a bad sleep last night as a result!"
CCTV picked up Williams again on the day of the murder, before and after Ms Hartley was paralysed and butchered in her own home.
Earlier that day she had arrived at work at the Chill Factore dry ski slope in Manchester but pretended to vomit and went home on sick leave as an alibi.
She claimed to the jury she had been ill in bed at the time of the murder at around 7pm.
Williams used tape to alter the number plate on her Renault Clio before she drove off to stab her love rival to death.
She was captured on CCTV arriving at Ms Hartley's home before calmly leaving and driving away.
Ms Hartley suffered 24 stab wounds - six to the head and neck, four to her right arm, five to the back, five to the front of the chest, two to the abdomen and two to the right leg.
She also suffered multiple cuts. One to her face, five to her right arm, nine to the left arm and two to the torso. There were also two puncture wounds to her head.
The pair - who had purchased 'burner phones' to communicate with each other - then met around 50 miles away in a car park in Ellesmere Port, before dumping the Clio and driving away in Walsh's Vauxhall Astra.
It’s unclear who was driving but it took around an hour and a half to return to Williams’ home in Chester.
Walsh left there around midnight.
Prosecutors described the moment they arrived home as "mission accomplished" for the killers.
The court heard in the aftermath of the "orgy of violence" in which Ms Hartley was killed, the pair met again to watch and sing along to Abba film 'Mamma Mia'.
John McDermott QC, prosecuting, said the murder plot was "the stuff of spy novels".
Walsh refused to give evidence at Preston Crown Court while Williams claimed she was an "easy-going" woman who had nothing to do with the murder.