A primary school teacher, Amy, 32, was chased out of her home by her husband, Daniel Appleton, 37, and he attacked her on the driveway wearing only his boxers.
An old woman, Sandra Seagrave, 76, who tried to involve herself in the situation was beaten up by Daniel with her own walking stick.
As she lay stricken on the ground, Appleton returned to his wife and struck her with the same stick as she tried to hide, jurors were told.
The garage owner then told a witness: “I know I’ve killed my wife and I know I am going to prison.”
He was also heard screaming “I could murder you” by neighbours moments before the attack, the court heard.
Police found Appleton covered in blood inside the marital home in Crawley, West Sussex.
He had stabbed himself at least five times in the chest with a kitchen knife in a botched suicide attempt.
Appleton was rushed to hospital, while both Amy and Sandra were declared dead at the scene just days before Christmas.
‘INTENT ON MURDER‘
Jurors at Hove Crown Court heard how Appleton has admitted manslaughter but denies murder.
He claims the double killing was the result of a “psychotic episode”.
But the prosecution say he was high after taking a synthetic form of LSD and was “intent on murder”.
The court heard Appleton had married Amy in October 2018 after 13 years together.
They had recently returned from honeymoon when the Copthorne Junior School teacher was killed.
‘I’M F***ING DONE WITH THIS‘
On the day of the attacks, neighbour Ivonne Greenwell heard Appleton shouting “I’ve had f***ing enough of this” and “I’m f***ing done with this”.
She then heard him scream: “I could murder you”.
The neighbour dialled 999 as she saw Appleton walk down the driveway in his boxers and attack Sandra with the stick at full force, it was said.
Searches on his phone later showed he had searched for “worse mushrooms, worse mushrooms trip, bad mushrooms trip stories and strongest mushrooms” just 11 days before the killings.
Forensic analysis of Appleton’s hair and nail clippings also showed traces of 25i-NBOMe – a powerful synthetic hallucinogenic similar to LSD – plus mephedrone.
‘BEAT HER TO DEATH‘
Experts believe both drugs could have been responsible for his violent psychotic behaviour and may have been present at the time of the attacks.
Prosecutor Nicholas Corsellis QC said: “The defendant pursued his wife Amy out of their home and began to assault her on their driveway.
“Sandra Seagrave, a slightly built lady aged 76, standing 4’9” in height was on her morning walk using a walking stick to assist her.
“She saw what was happening and intervened by speaking to the defendant no doubt in order to protect Amy Appleton.
“The defendant reacted by turning his aggression on her. He did so verbally at first, but then by taking her walking stick from her and beating to her death with it.
“He then returned with the stick to his wife, who was probably trying to hide from the man she loved, and proceeded to beat her to death with it too.”
The trial, which is expected to last several weeks, continues.