Neighbours watched on as a man beat a pensioner and his own wife to death on a quiet suburban street on a Sunday morning, a court heard.
Sandy Seagrave, 76, had stepped in to stop Daniel Appleton, 37 beating his wife, Amy, 32, on the driveway of their semi-detached home, a jury was told.
But as she confronted him the car mechanic grabbed her walking stick and hit her over the head causing her to fall to the ground, a court heard.
Testifying neighbours said they watched on as Appleton then beat the 4’9″ pensioner to death.
Appleton, who ran a garage business, then turned his attention back to his wife, Amy, a teacher, who was in her underwear and trying to hide behind the Audi car on the driveway.
He approached her and beat her death with the same walking stick he had used to kill Miss Seagrave, the jury was told.
Appleton is on trial at Hove Crown Court for the double killing which happened in Crawley, West Sussex, just three days before Christmas last year.
The defendant admits killing the women but denies murder, claiming it was the result of a psychotic episode.
Prosecutors say traces of psychoactive drugs were found in samples taken from him and he may have been high on a synthetic form of LSD.
Today Ivonne Greenwell, who lived next door with her husband and two children, said the attack was “terrifying” and “mindless”.
She said she first heard an “explosive” commotion coming through the party wall of her semi-detached home as she lay in bed.
Mrs Greenwell, a dental nurse, told Hove Crown Court she could hear Mr Appleton screaming at his wife at the top of his voice while his wife tried to comfort and calm him down.
She said: “He was screaming and he said ‘I’ve had fing enough of this, I’m fing done with this.’
“I looked at my phone and thought shall I phone the police now.
“Then he said ‘I could do a murder. I could murder you.’
“I ran to my daughter’s room. My daughter was stood in her bedroom stiff with fear.
“I phoned 999 immediately and I got a lady on the phone and I basically yelled ‘You’ve got to come to this address. My neighbours are having an argument that is rapidly getting out of hand’.”
Mrs Greenwell said she went back to her bedroom window expecting to see the police “screeching” around the corner.
Instead she saw Appleton walk out of his house down his driveway dressed just in white boxer shorts.
She said: “His chest was sort of puffed out and he this stance that almost said ‘Does anyone want to have a go at me?'”
Mrs Greenwell then saw Sandy Seagrave, 76, dressed in a purple overcoat and carrying a walking stick, crossing the road towards Appleton.
She said a verbal altercation broke out between the pair and the pensioner lifted up her stick and said: “How dare you!”
She told the court that without warning Appleton grabbed the walking stick out of her hand and hit her over the head causing Mrs Seagrave to fall to the ground.
“There was no noise,” she said.
“It happened in a flash and she was on the ground motionless. She did not move.
“She did not say anything. I was on the phone to the emergency services.
“I banged my hand on the window a couple of times and shouted ‘Stop it Dan, Stop it. Don’t do it.’
“He then took the walking stick in both hands and with full force hit Sandy over the head.
“I screamed ‘He was killing her, that he had hit her.’
“My daughter was standing next to me.
“She could see the verbal altercation and she saw him snatch the walking stick from Sandy and she saw him raise the walking stick and then she ran away to her bedroom and hid under the blankets.
“It was too horrible to watch so I turned around and left my bedroom.”
Janet Spragg, who was out on a morning run with her Dalmatian, said she stopped as she saw Mrs Seagrave approaching Appleton.
“You could tell she was not happy and was telling him off and he was walking towards her,” she told the court.
“He was much bigger than Sandy. He was quite upright. He was quite determined and there was an altercation.
“She was going over to tell him off about something and his language was bluer and was more aggressive. There were expletives.
“She wasn’t intimidated. She walked towards him. He took the walking stick, he did it very quickly. I thought ‘Why would you do that?'”
Mrs Spragg said she watched as Appleton then hit the pensioner with the stick.
She said: “It was a very quick act and with all his force he hit her in the stomach, with force and she just collapsed.
“The force was so disproportionate and that is when I shouted out ‘No!'”
Prosecutors claim Appleton had taken a synthetic form of LSD and was high when he launched the attacks.
The court heard that in an interview with a psychiatrist Appleton admitted having taken magic mushrooms – a natural hallucinogen – years before.
Forensic searches of his mobile phone found that just 11 days before the killings he had searched for ‘worse mushrooms, worse mushrooms trip, bad mushrooms trip stories and strongest mushrooms’.
Nick Corsellis QC, prosecuting, said hair samples and nail clippings subsequently taken from the defendant showed the presence of 25i-NBOMe – a highly potent synthetic version of LSD – and mephedrone.
The trial continues.