A Good Samaritan who intervened in a street row was murdered when her assailant thrust a broken wine bottle into her neck, a jury has heard.
Mother-of-two Alison Wilson, 36, was concerned for the safety of a baby whose mother was arguing with Stephen Duggan, 28, near a chip shop in Widnes, Cheshire.
Witnessing the argument from a taxi with a male friend she thought it would be "less intimidating" if she stepped in as peacemaker, Liverpool Crown Court was told.
She failed to stop the row and then Duggan allegedly turned on her and her friend as he used the bottle as a weapon.
He felled Anthony Tomlinson, 43, with a blow to the side of the head and then thrust the now broken bottle into his face before he went on to push it into the area of Ms Wilson's left neck which severed her jugular vein, the court heard.
Despite being treated quickly by paramedics and doctors following the incident on the evening of March 7 this year, Ms Wilson died in hospital six days later.
Opening the prosecution case, Gordon Cole QC said: "We say that night this defendant was the aggressor. We say it was he who lost his temper. We say it was he who deliberately attacked both Alison Wilson and Anthony Tomlinson.
"This was, we say, not some sort of accident he (Duggan) may seek to make out.
"We make it clear we do not say he intended to kill Alison Wilson but we do say he intended to inflict really serious harm because to use a broken bottle to her head and neck when she presented no threat whatsoever shows he had lost his temper."
He added Duggan issued no threats or warnings before he was said to have wielded the bottle.
Duggan, formerly of Water Street, Runcorn, had previously pleaded guilty to the manslaughter of Ms Wilson but the Crown did not accept the plea, the jury was told.
He denies murder and further counts of wounding with intent and assault occasioning actual bodily harm.
Mr Cole said Duggan had been drinking wine and bottles of Desperado beer earlier in the evening when celebrating the prospect of a new job at the firm his father worked for.
Later he became "argumentative and aggressive" as he stormed out "in a mood" from his father's home in Bellhouse Lane, Widnes, taking a bottle of wine.
A heated argument in nearby Frank Street followed at about 11.20pm with the mother carrying her young child who had both earlier been at the celebration.
By this time Ms Wilson and Mr Tomlinson had stopped off in a taxi to get a takeaway and saw the ensuing row.
The prosecutor said: "Having suggested the taxi slow down, Anthony Tomlinson shouted something like 'is everything OK, what's going on?' and he said he should go and try to calm things down.
"In fact, Alison Wilson suggested it was better if she went to calm things down. She was the mother of two children of her own. She thought it would be less intimidating if she sought to calm things down."
Mr Tomlinson later approached Duggan with a takeaway in one hand and Ms Wilson's handbag in the other, the jury was told.
Mr Cole said: "Having got closer to the defendant, Mr Tomlinson may have said something like 'what's happening?' because the defendant was heard to say 'never mind what I'm f***ing doing, what are you f***ing doing poking your nose in my business?"
The Crown say Duggan then launched the two separate "deliberate and unprovoked" assaults on the pair, as well as punching the young mother during the incident.
The young mother was heard to have screamed "Oh my God, what are you doing" as the defendant struck Ms Wilson, the court heard.
When Mr Tomlinson regained consciousness he saw his friend holding her hand on her neck with blood coming between her fingers.
Paramedics treating Ms Wilson said she had suffered "a catastrophic injury", while Mr Tomlinson suffered a cut which went "clean through" his left cheek.
The defendant left the scene and was arrested in the early hours of the following day when police officers pushed the wanted man off his bicycle in Widnes when he failed to stop for them.
Duggan admits wounding Mr Tomlinson but not with intent to cause grievous bodily harm.
He has pleaded guilty to assaulting the young mother but denies assault occasioning actual bodily harm to the baby who was said to have fallen from his car seat during the argument. Neither can be named for legal reasons.
The trial continues tomorrow.