Graham Norton was stabbed and left for dead in the 1980s.
The 56-year-old chat show host admitted it was "touch and go" as to whether he survived the attack but says the epidemic of knife crime up and down the country doesn't leave him "triggered".
He said: "It was very serious. It was a mugging, I didn't even realise I'd been stabbed in that classic way, because your adrenaline is pumping. I looked down, and I saw all this blood. I lost a bit over half my blood. So it was very touch and go, I think."
The attack happened in West London in 1989, when Graham was a student at drama school.
And Graham admits he sees stabbings are so common that they no longer "trigger anything" inside him anymore.
He told the Daily Mirror newspaper: "They don't trigger anything now. I did have someone pull a knife on me again a few years after the first stabbing but there were people around and it was fine, it was outside a club. Somebody wanted money and had a knife. And what's so sad about the knife crime now is that everyone is a victim in the end.
"Because people are losing their lives and equally the kids stabbing people, their life is destroyed for nothing, for this stupid thing because they couldn't get their heads around the consequences. In the moment it was, 'I want that phone' or 'You've got the keys to the car I want to steal.'
"I think it's a lack of imagination in the end, that if you had the empathy, that level of imagination to think it through, that the person you're stabbing could be a brother friend sister, mother or father, you wouldn't do it. Somehow people have been dehumanised."
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