TV presenters are accustomed to interviewing individuals from every background, though it's perfectly understandable that some encounters will prove more pleasant than others.

While numerous celebrities are utterly delightful, it's frequently commonplace to experience 'diva' conduct from stars who make executing the role challenging.

Given Graham Norton has worked as a TV presenter for three decades, having launched his major debut in 1996, he has met countless celebrities throughout his professional life.

Prior to the star's 63rd birthday, we examine the celebrities he described as most 'difficult' to interview.

This includes the star that dominates his list for 'worst' interview.

Norton, from Dublin, Ireland, officially identified Wahlberg as his "worst-ever" guest. During a 2013 appearance on BBC's The Graham Norton Show, Wahlberg arrived sober but became severely intoxicated approximately 15 minutes into the programme.

He continuously interrupted fellow guests Michael Fassbender and Sarah Silverman, sat on Norton's lap, and ultimately fell asleep on the sofa while Fassbender was telling a story.

Norton told The Mirror: "The famous (worst guest) was Mark Wahlberg, I guess. He was fine when he came on the show. There was not a hint of it and then about 20 minutes into the show (alcohol) caught up with him. Oh it was bad. At one point Mark was asleep on the couch in front of the audience."

He elaborated on his nightmarish experience with Wahlberg at Henley Literary Festival 2025 on 10 October, where he informed the audience: "If you ever see a drunk person on the show, it's because they've arrived drunk - we have not made that happen.

"Mark Wahlberg was a weird one because when he arrived, he didn't seem drunk. He told me about his film, told me a couple of stories about stunts going wrong or whatever, and then it was only 15 minutes into the show when whatever the hell was in his system really took hold - and it was hell."

Michael Fassbender and Sarah Silverman were also overwhelmed by Wahlberg's behaviour, Norton said, as he went on: "No one could tell a story. You tried to tell a story, he'd just interrupt and, at one stage, Michael Fassbender was telling a story and this one was going quite well.

"He was really getting into the heart of the anecdote. I thought, 'This one is going well - I wonder why' and I looked over at Mark Wahlberg and he was asleep."

Alongside Wahlberg, the television host also characterised fellow actor Robert De Niro as a "benign presence" who was merely an inadequate storyteller. One tale was so protracted and meandering that De Niro ultimately enquired, "Why am I telling this?" before the segment was completely removed from the broadcast.

Norton has also previously remarked that he found US actor Kevin Costner "snooty" and discourteous. He told The Express: "I ask him a question and he looks at me like 'Jesus, do I have to talk to this man?' He kind of gives a half-a*** answer and Helen Mirren chips in and asks him a question and he could not be happier."

Actor and professional boxer Mickey Rourke was labelled "exhausting" and a "nightmare" by Norton. The star reportedly turned up with a half-empty bottle of Jack Daniels to filming and repeatedly lit cigarettes throughout the recording.

Norton told the New Zealand Herald: "Mickey Rourke he was just exhausting because he wanted to smoke all the time. I'd turn away for a second, turn back and he'd have lit another cigarette. It was so boring - you feel like a teacher taking children on a school trip, not a chat show host."

Norton also recalled his interview with 1970s pop icon David Cassidy as amongst the most unpleasant experiences of his career. He described the late singer as "bitter and weird" during their encounter.

While appearing on This Morning, Norton spoke to presenters Eamonn Holmes and Ruth Langsford regarding the occasion Cassidy featured on his programme.

Norton elaborated on why the meeting was so dreadful, stating: "I loved him when I was a teenager, and then you meet him, and he's so bitter and weird... not a happy time... I think David hates that he was David Cassidy."