A "CALCULATED and devious liar" tried to murder her sister by torching a house while she slept upstairs where she would be "trapped" and would "burn alive" a court has heard.

Cathy Bartlett set the fire by pouring a can of petrol on the stairs, having removed a working smoke alarm and its battery, it was claimed.

Prosecutor Charlie Gabb QC told jurors at Winchester Crown Court how he believed it was the second time in a month that Bartlett, 30, had sparked a major fire to try to kill her sister Rachael.

The motive was to cover up her "dishonesty and treachery" to her sibling, fearing she was about to be found out having spun a web of lies, stolen more than £100,000 of her money which she lavished on friends and acquaintances and created a fake life for herself.

The court heard how a month before the blaze at Bartlett's mother's home in New In Lane, Bartley, a fire had ravaged her father's three- bedroom home in nearby Winsor.

Rachael had been living there alone at the time, with her dog Jade, and only survived the extreme fire thanks to the animal alerting her. Jade died in the fire.

As he opened his case for the prosecution, Mr Gabb told how the blaze in Bartley, broke out on Tuesday April 7 - the morning after Easter Monday - as her mother Frances slept in the front bedroom and Rachael was asleep upstairs.

Mr Gabb told jurors how Bartlett had been working as finance manager for Rachael and was in complete control of all her finances which she allegedly plundered - including spending £20,000 on Saints tickets she gave away to friends.

He told how she waited until the early hours for her mother and sister to be asleep before pouring a can of petrol on the stairs around 2.30am.

"She had been driven in her own mind to the point of doing something desperate. Within the space of the next 12 hours her world was going to be exposed. She was going to be revealed as the lying, cheating, treacherous sister that she was."

Mr Gabb added: "The Crown would say that's wasn't the first time. She had tried before and failed. This time it had to work."

He continued: "She went outside to her car and she took from inside a petrol can. She went back into the house. She knew what she was going to do, this was preparation. It's almost unimaginable, burning your own sister alive in the house."

Jurors heard how upstairs Rachael was in bed, having been purposely given alcohol and tablets to ensure she slept "and would never wake up" said Mr Gabb.

Bartlett "sprinkled" the petrol on the stairs, four from the top, before she "struck a match and set the fire".

Mr Gabb told the court: "Rachael was not meant to get down those stairs."

He then described how Bartlett, who is said to have disposed of the petrol can in a garden bin, then turned herself into "a sort of heroine" rushing to her mother's bedroom to wake her before they both escaped the burning house.

Jurors were told how the pair went to the back of the house, with Frances screaming out while Bartlett was "calm".

"They had saved themselves. Mum was shouting out and screaming. She didn't know what Cathy Bartlett was doing."

Mr Gabb told how Rachael, who is "a large lady" recovering from a badly fractured ankle, woke from the noise but was met with the flames licking the top of the stairs. Her only escape, he said my was a Velux loft window, adding "you can only imagine....she feared it was going to be her funeral pyre."

Jurors heard how Rachael pulled her bed underneath the window and somehow got out on to the roof, clinging on before she lost her grip, fell to the ground and was knocked out.

Mr Gabb said: "You can do an awful lot when you think the end is nigh. It must have taken supreme effort to do what she did."

The court heard how Bartlett - a mum of two young children - had started the fire and attempted to kill her sister because she was hours away from her "tangled web of lies" being uncovered.

Later that day Rachael had arranged for a meeting at the bank and was set to see, for the first time, that her bank accounts had been "raided" jurors were told.

Mr Gabb described how Bartlett had made the 999 call to alert the fire service to the blaze at 2.38am, emergency crews arrived and Rachael was taken to hospital.

But as fire investigators examined the scene they called in police after fire sniffer dog Ruby, twice identified that petrol had been found on the stairs.

Mr Gabb told how there was evidence found that was "highly incriminating" of Bartlett who, he says, will plead as her defence that she didn't start the fire - but her sister Rachael did.

He told jurors: "You may ask why on earth Rachael would want to commit suicide in that horrific way."

The court heard how search teams made a "shocking discovery" when they swabbed the petrol can found discarded in a garden bin and found Bartlett's DNA on it.

They found a smoke alarm, minus the battery, which was later recovered from the kitchen, swabbed and found to also have Bartlett's DNA.

A box of large matches were also found containing her fingerprints, the court heard.

Mr Gabb said: "Somebody had taken the trouble to get on a chair and take the battery out of the smoke alarm so it wouldn't work. Nobody was meant to get out of that property. The fire was meant to be of such an intensity it was too late."

Police uncovered "dishonesty and treachery from one sister towards another" when they began investigating.

"Up until that time Rachael Bartlett believed that her sister love her as much as she loved Cathy," he added.

Jurors went on to hear about an earlier fire, on March 6, at the home of Bartlett's father Michael, in Whitemoor Lane, Winsor.

At the time, Rachael was staying there alone, with her dog Jade, and the blaze was so ferocious that around 95 per cent of it was destroyed.

Mr Gabb told the court that no charges were ever brought following the fire as all evidence had been destroyed, but added that although the prosecution could not rule out a genuine accident, Bartlett was "a prime suspect".

Explaining what he believed to be Bartlett's motive, he described her as "just plain bad or some may say evil" for what she did in a bid to evade her lies being uncovered.

He told how Bartlett had begun working for Rachael in 2014, after she started up her own company called NurtureItGlobal, a company that brings businesses together, based at their father's property.

Bartlett, trusted by her sister, was hired as finance manager to look after the books and accounts but behind her sister's back what she did amounted to "systematic greed", he said.

What happened then was described to jurors as "breathtaking dishonesty" as she created a fictional character called Rick McCarthy who Bartlett claimed had signed a contract to do business with the firm, bringing in £60,000 a year.

Emails and letter were exchanged and Bartlett said she was working for him directly, because he thought she was so impressive, for three days a week.

But, the court heard, the entire thing was fantasy - McCarthy didn't exist and the whole thing was "a figment of her warped and dishonest imagination".

Jurors were told: "Cathy Bartlett was conducting a private life completely removed from the norm. She was about buying friends."

Mr Gabb told the court how, unbeknown to Rachael, she bought more than 24,000 football tickets and had a "guest list" of mates and her lover, who she took to Saints games on hospitality tickets with free food and drink.

She also put up many friends in Southampton's Grand Harbour Hotel, enjoying room service having told staff there that she worked for Southampton Football Club to try and get a cheaper deal.

Bartlett also spent her sister's cash - over £1,300 - on expensive vodka she then sold off to friends cheaply or gave away, and booked and paid for 12 tickets and three caravans at the Isle of Wight Festival, the court heard.

Mr Gabb said: "Rachael knew absolutely nothing.... It was just staggering. That was her, buying friends, making people think she is something she is not."

Bartlett, who has been on remand since she was charged, denies attempted murder, arson with intent to endanger life and 10 counts of fraud.

Proceeding.