SARAH Williams and Katrina Walsh spent 17 months planning what they thought was the “perfect murder”.

Thinking they were acting out a real life version of Walsh’s favourite TV show Hunted - where contestants try to evade capture by expert trackers - they believed their bloody assassination would be a mystery hapless cops would never be able to solve.

But the further they went to cover their tracks - the more moronic mistakes they made.

Far from being clever killers - the pals were in fact just bargain basement murderers who left a clear trail for police to follow.

The pair were today found guilty of the murder of successful businesswoman Sadie Hartley, 60, after shooting her with a 500,000-volt stun gun as she answered the door at her home.

The pair were each handed life sentences this afternoon with Williams to serve a minimum of 30 years behind bars, Walsh a minimum of 25 years.

Williams, 35, carried out the sickening crime to fulfil her obsessive desire to be with Hartley’s partner Ian Johnston.

She was previously in a relationship Johnston, 57, but it ended when he refused to leave Hartley.

During the six-week trial, Preston Crown Court heard how Williams drove to Hartley's home in Helmshore, Lancashire, on January 14 and incapacitated her with a 500,000-volt stun gun before knifing her to death with ‘demonic savagery’.

Williams’ accomplice Katrina Walsh was also found guilty of the murder of innocent Sadie.

She had bought the murder weapon, the stun gun, a tracking device and a getaway car for the night of the murder.

Chief among their idiotic errors was the fact that Walsh left a DIARY detailing almost every detail of the murder conspiracy, including plans of potentially killing Sadie with a motorbike and leaving an IS flag at the scene of the murder to throw detectives off their scent.

The bungling criminals bought a GPS tracker to follow Williams’ ex Ian Johnston so they could find out where he and Sadie Hartley were living.

Little did they know that the tracker also kept a log of THEIR movements.

Tied in with scores of CCTV images, car number plate cameras and phone mast evidence in the months leading up to the murder, police were able to piece together a complete picture of their movements before, during and after the killing.

They were caught on CCTV buying the kitchen knife murder weapon - bought on Walsh’s Tesco Clubcard.

Williams and Walsh even bought the stun-gun from a German dealer as part of a “buy-one-get-one pepper-spray-free” offer.

Then, once the penny dropped and the net was closing in on them, the best mates panicked and  turned on each other.

Walsh just couldn’t stop blabbing to the police, showing them where she had stashed the murder weapon and telling them all about her “dangerous” friend Sarah.

Outlining the whole sorry tale to the jury, prosecutor John McDermott QC said: "They’d fancied themselves as Batman and Robin for years - but on the wrong side of the law.”

He described Williams after her arrest, saying: “It began to dawn on her that she had not - after all - committed the perfect murder.

"She was asked about cell siting evidence that had been obtained. They asked her questions about CCTV evidence, photographic evidence, the stun gun and the trip to Germany, about Kit and her diaries.

“She was asked to account for Sadie’s DNA being found in her bathroom and about a tracker fitted to Ian’s car.

“As it dawned on her that the evidence was gathering to all of those questions the more she answered ‘no comment’.”

Of the tracker error the barrister said: “What they almost certainly didn’t know was that the company which sold them the tracker also keeps a record of where the tracker goes.”

In what they must have thought was another genius move, Williams and Walsh even tried to buy a car specifically for the murder - but did all their “reconnaissance missions” in Williams’ Volvo.

And “burner” phones bought by them to communicate specifically about the “evil” plot were quickly and easily linked directly to them by police and so called "cell site" experts.

The pair were captured numerous times on CCTV in Sunnybank Road, Helmshore, as they scouted out their mission and Williams was even caught on camera just before she carried out the murder - which took her four minutes and forty seconds to complete.

They were also caught buying the knife and flowers at a local Tesco and Williams was dumb enough to wear trousers with a distinctive reflective strip on them - enabling her to be picked out quite easily even on grainy CCTV footage.

When it came to the “clean up” following the murder the useless duo thought basic washing up liquid would be enough to clean DNA out of the footwell of the murder car after Williams had stepped in Sadie’s blood during the savage killing.

It wasn’t. And Sadie’s DNA was also found in Williams’ bath and on a pair of her sunglasses.

When their plan very quickly began to unravel a panicking Katrina was the first to break blaming the murder on Williams and trying her best to appear like a weak-minded “patsy” with amnesia.

She pointed out where she had tried and failed to burn the knife and the clothing in a pit on a farm where she worked, telling them: “I might have done something, I might have done something, I might have done something. I just don’t remember.”

Luckily the jury didn’t have to rely on the memory of a murderer - they could just read her diaries instead.

ALL A GAME FOR KILLER

PSYCHO murderer Sarah Williams identified with a Game of Thrones character called the Red Woman - a priestess who uses sex to snare men and get them to do her bidding.

Williams’ trial heard how she bombarded her “ideal man” Ian Johnston with scores of “filthy” and explicit sex texts - included lewd photographs of herself - to win her way back into his affections.

All the while she was plotting with her best pal Katrina Walsh on how to “take out” Mr Johnston’s partner Sadie Hartley.

Walsh told cops that Williams - who claimed to be reading Game of Thrones in bed at the time of the slaughter - was basing herself on the Red Woman, also known as Melisandre, from the hit show.

She claimed the pair engaged in  “knife practise” while planning “Operation Scare the Bitch Senseless” and the “Assassination of the Bitch”.

Walsh told cops: “I’ve stood there and had the knife drawn across my neck. I’ve stood with Sarah behind me and she’s drawn the knife right round.”

At one point in the knife practice Williams is alleged to have said: “The night is dark”.

Walsh was then “supposed” to reply with the expression “And full of terrors”.

Walsh told detectives: “I think it comes from Game of Thrones. I think she’s being Melisandre, a very, very evil witch in Game of Thrones.

“I think she’s warning me…I think she’s a psycho and I think she’s almost identifying herself as Melisandre. I was in mortal dread of her”.

In Season 2 of Game of Thrones Melisandre stands on a beach conducting a ceremony for her god, the Lord of Light.

She intones: “The night is dark and full of terrors” and the crowd of onlookers repeat her words.

Melisandre predicts that a heavy darkness will fall on the world in the wake of the long summer, that stars will bleed while the cold breath of winter will freeze the seas and says that the dead will rise in the north.

The Red Woman is also famous for getting naked in the show and using her sexuality to wrap various male characters around her finger.

During the trial Williams was also accused of using sex  as a weapon.

Tony Cross QC, defending Walsh, accused Williams of “preying” on Mr Johnston in the weeks leading up to the killing, sending him explicit text messages of her “legs akimbo” wearing just a pair of boots.

He said: “You were using sex to try and snare him.”

Williams replied: “No.”

The barrister added: “You were pursuing him weren’t you?”

Williams said: “I was pursuing him sexually, yes.”

The QC said: “You were preying on him”.

Williams’ obsession with Game of Thrones apparently even led her to get a photograph next to a raven while on a trip to Germany to buy the stun-gun which was used to paralyse Sadie before she stabbed her to death.

Ravens are a major symbol of the show.

Walsh and Williams also shared love of witchcraft and the occult. Williams “liked” the Facebook pages for numerous witchcraft, pagan and wiccan groups.

Pages including Wiccan By Nature, The Conjuring of a Dark Witch, Witch's Secret and Witch were all found on Williams’ feed.

Meanwhile one worried pal of her partner in crime - Katrina Walsh - said she thought the horse riding instructor may have got into SATANISM when her world unravelled after her husband dumped her for a younger woman.

The pair even consulted mystic, fortune telling Tarot cards as they plotted the killing of innocent businesswoman Sadie Hartley.

Walsh - known as Kitt to her friends - was a biker and into heavy metal and proudly advertised her love of black cats and bats in her front window.

The murderers grew especially close when Williams, 35, provided a shoulder for Katrina to cry on during the painful split from husband Kev Walsh.

One woman, who knew horse riding instructor Katrina well, said: “She was very private. We met her through the horses and she was very horse and animal orientated.

“Her husband went off with a younger woman and she never got over it. She bought a brand new Harley Davidson and went on Route 66 in America to try and get over her heartbreak.

“She was never the same after it really. She lost all her hair and always wore a cap.”

The friend said Katrina and Kev used to be in motorbike gangs and was into heavy metal.

She said: “She was a headbanger. You would go for a beer at the local pub and she would be there for three hours straight – constant headbanging!

“I always thought something would go wrong in her head because of it.”

She said this was in 2006 at the Red Lion in Little Sutton, Cheshire, close to where Walsh lived and worked.

The pal added: “Before it she was a very strong alpha woman. Her and Sarah were very close and it was a bit weird.

“I am not shocked by what's happened. I have seen Kitt at her lowest of the low when she went through that divorce and she did make me worry.

“She went very strange. She joined some group, I think it was called the Vipers. And she got a tattoo. I thought it had something to do with Satanism.

“I just knew she could be capable of something.”

The Sun also discovered how both Kev Walsh and Williams “liked” the Facebook page of Witchcraft, Paganism, & Wicca.

The page - which has 460,000 “likes” - says: “This page is for all Pagans and Witches, whether you are Wiccan, a Witch, Asatru, Druid, Reconstructionist, Animist, Polytheist, Pantheist, Shaman, Kemetic, Hellenic, any other Pagan path, or just someone who is curious about Paganism.

"It is a place to connect with other like minded individuals and to learn from one another. It is also a page to educate those who are interested in Paganism, new, or those who aren't Pagan but want to understand our paths.”

Another woman, whose daughter used to get riding lessons from Katrina, said: "She was a biggish girl. Very butch. I don't think she had many friends. She didn't come across as popular. She was odd. Very odd. Just an odd woman. I just thought she was strange."

Walsh’s neighbour Wendy Costelloe, 64, said people were unsure of her and Kev at first when they first moved into the village.

"None of us were very keen on him. He wasn't a nice person, he was odd,” she said.

"They were both big bikers. They rode Harley Davidson motorbikes. He was a big bloke with a beard and she was covered in tattoos.

"I was totally shocked that she was even arrested and had anything to do with it but you don't know people do you.”

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