WATCH: Robert Downey Jr walks out of interview with Channel 4's Krishnan Guru-Murthy
Channel 4 reporter Krishnan Guru-Murthy strikes again as another star reacts badly to his line of questioning.
Avengers: Age of Ultron star Robert Downey Jr walked out of an interview with Guru-Murthy when the interviewer persisted in asking questions about the star's previous problems with drugs and alcohol and asked about his father.
Downey Jr appeared to be blind-sided by the personal questions as he was being interviewed as part of the press junket for Avengers: Age of Ultron, in which he plays Iron Man.
At one point he asked the interviewer, "Are we promoting a movie?"
Asked about a New York Times interview where he said you could not go to jail and "come out a liberal", he replied to Guru-Murthy "I could pick that apart for two hours and be no closer to the truth than giving you some half-arsed answer right now.
"I couldn't even tell you what a liberal is."
When the personal questions continued and he was asked about his relationship with his father, Downey Jr upped and left, saying, "I'm sorry, I really don't ... what are we doing?"
Downey Jr is not the first Hollywood star to be upset by Guru-Murthy's interview technique - last year director Quentin Tarantino objected to his line of questioning.
He said: "I'm not your slave and you are not my master. You can't make me dance to your tune. I'm not a monkey."