It's not safe, and he's in agony: in one of the many highlights of his 45-year film career, Dustin Hoffman is being tortured by a sadistic Nazi dentist played by Laurence Olivier. In the harrowing interrogation, from the Seventies film Marathon Man, the terrified Hoffman doesn't understand the question, much less have the answer. Despite A-list Hollywood status and a back catalogue of more than 50 films, he admits his life off-screen is almost as fearful and confused.
The star refers to himself as a "freak accident", battling the "demons" that plague him. Despite all his success and awards, including two Oscars, five Golden Globes and three Baftas, his life has been marred by self-doubt. He is a great believer in therapy, something he says "is the imperative. It's saved me." Asked if he means that literally, he says "yes, yes", before swiftly changing the subject.
Speaking ahead of next month's release of Quartet, his first film behind the camera, the 75-year-old actor explains why he took so long to make the move. "I don't think 35 to 40 years is that long to make this decision, if you have my demons... I really believed I was a freak accident when I became famous after The Graduate. It wasn't meant to be."
Hoffman, whose directorial debut is a bitter-sweet comedy set in a retirement home, says: "I felt I wasn't entitled to be able to do anything else... I didn't want to push the envelope."
He "barely survived" his childhood, the actor says on BBC Radio 4's Desert Island Discs, being broadcast today. His parents had wanted a girl. When he was born, "they didn't even have a name for me. I think they picked the name out of a magazine."
It was a motivation to "meet girls" that drove him into acting. "I was short, filled with acne, literally told I was unattractive. I didn't have any girlfriends."
Success took years to achieve – he was 29 when he was cast as Benjamin in The Graduate. It nearly didn't happen – he thought the part was perfect for Robert Redford. "I didn't want to audition for it," he admits.
"Mrs Robinson", the Simon & Garfunkel hit from the 1967 film, does not make it on to his list of favourite tracks to take to the desert island.
The actor, who dreamt of being a jazz pianist before realising he "didn't have the talent", picks "Frim Fram Sauce", sung by Diana Krall. One of the lines, "with shifafa on the side", brought back the pain of his past: "I didn't want to eat when I was growing up. I would be told to eat this particular dish that they gave me because it had shifafa, which meant it was delicious... I hadn't heard the word in 70 years. I burst out crying."
Another, "Shoot the Breeze", sung by Bette Midler, was written by Hoffman after breaking up with a girlfriend. And he picks the Sixties pop song "Memphis" by Donnie Brooks, as it lifted him on a day he was "particularly depressed".
He reveals how his portrayal of Willy Loman, in a production of Arthur Miller's Death of a Salesman, was based on his father, who became a furniture salesman after being sacked as set decorator at Columbia. "I hoped he wouldn't put it together that I was making a comment on him, and the first thing he said to me was: 'Boy, that guy is some loser.' I've never forgotten that."
The fear that each job could be his last is ever-present. "If it took you years and years to get your first job, the feeling is that this is your last; you're not going to be asked again."