An IT consultant on a day out with his son was stabbed 18 times and died following a row with a man on a train, a court has heard.
Darren Pencille, 36, is said to have knifed 51-year-old Lee Pomeroy in the neck during an argument on the Guildford to London Waterloo train on January 4.
Mr Pomeroy, who would have celebrated his 52nd birthday the day after the attack, was on his way to the capital for a day trip with his 14-year-old son.
He died on the platform at Horsley station a little over an hour later, the Old Bailey heard today.
The court was told the row is thought to have started when Pencille accused Mr Pomeroy of blocking the carriage's aisle.
Pencille called Mr Pomeroy a 'c**t' and a 'pu**y' before the victim was heard telling him 'you shouldn't have humiliated me in front of my kid,' witnesses said
Lee Pomeroy was attacked and killed on a train from Guildford to Waterloo in January
Darren Pencille started arguing with Mr Pomeroy minutes after getting on the train, apparently over whether Mr Pomeroy was blocking the aisle
Prosecutor Jacob Hallam QC told jurors: 'On Saturday January 5, Lee Pomeroy was to celebrate his 52nd birthday.
'At 1.01pm on Friday January 4, Mr Pomeroy and his 14-year-old son boarded a train at London Road Station in Guildford, in Surrey, bound for London Waterloo. Lee Pomeroy did not leave that train alive.'
Mr Hallam said both Pencille and the Pomeroys boarded the train within seconds of each other, albeit through different doors.
Moments later, an argument broke out between the two men, apparently over whether Mr Pomeroy was blocking the aisle.
The prosecutor said: 'As he made his way down the carriage it may be that one or both the Pomeroys were blocking his way, because Mr Pencille chose to say something to them, and the something that he said was perhaps a bit snide, because he said to them 'Ignorance is bliss'.
'And he didn't just say it once. It appears he said it twice.
'That prompted Lee Pomeroy to respond, to ask what it was that he meant by those words, repeated on the face of it twice.
'An argument began between them, and it was an argument that became heated, and it became heated pretty quickly.'
Mr Pomeroy was taking his son (pictured with him when he was younger) to London on the day he was attacked and was heard saying: 'You shouldn't have humiliated me in front of my kid'
Both Pencille and his girlfriend, Chelsea Mitchell, are on trial at London's Old Bailey
Witnesses gave different accounts of snatches of the row they had overheard.
Two passengers sitting together reported hearing Pencille calling Mr Pomeroy a 'c**t' and a 'pu**y', with one saying he 'was the aggressor'.
Pencille is also said to have threatened: 'You touch me, you touch me and see what happens at the next stop.'
The court heard Mr Pomeroy demanded an apology, replying: 'You shouldn't have humiliated me in front of my kid.'
Both men were shouting at each other and Pencille became 'very