When you want to really mess someone up/would have really beaten someone silly.
“you’re getting me so pissed off, I really want to William Hurt You”
‘William Hurt You’, the act of someone losing their temper with someone else and warning them.
“I swear, if you keep winding me up I’m going to really ‘William hurt you’.
“Oh mate, I tell you, I was so close. I literally said ‘do that again and I’m going to ‘William hurt you’”.