Cosmologist Stephen Hawking's carer said that "working with Stephen is never dull" as she escorted him to the UK premiere of a biopic of his life.
Written and narrated by the 71-year-old author of A Brief History Of Time, Professor Hawking tells how he overcame severe disability to become the most famous living scientist in the world.
He attended a reception at Emmanuel College before a showing at the nearby Picturehouse cinema for the opening night of the Cambridge Film Festival.
As she helped him on his arrival, one of his carers, Claire Dutson, said: "I have worked with Stephen for 11 years - it has sometimes been harrowing but mostly fun.
"People see him as a renowned physicist but I just know him as Stephen, who has a great sense of humour."
Stephen Finnigan, the film's director, supported this description of the University of Cambridge professor.
He said: "Stephen was very different to how I imagined him to be.
"You expect him to be quite plain speaking, quite academic and quite brainy but actually you can have a laugh with Stephen Hawking.
"I went for a curry with him this afternoon and you can chat to him about anything."
In the trailer for the film, the University of Cambridge professor says: "This film is a personal journey through my life."
"I have lived five decades longer than doctors predicted. I have tried to make good use of my time."
Prof Hawking was diagnosed with amyotrophic lateral sclerosis, a form of motor neurone disease, when he was 21. He was told he had only a few years to live.
The film goes back to his childhood and his student days and shows him at home with carers.
It features interviews with his family, including his first wife Jane Wilde, along with friends and fellow academics.