In his 10th decade, the writer is as prolific as ever with a war film in the works and a new sex-fuelled novella set in a home for the elderly. He talks about mourning Maggie Smith, turning down a knighthood and what he makes of Donald Trump

Alan Bennett never expected to be writing in his 90s, with a novella published next week and a film in post-production. There was a time when he didn’t expect to reach 70. In 1997, a cancerous growth was found in his colon that had already begun to spread. “The surgeon didn’t think I’d got a chance, really,” recalls Bennett, 27 years on. “So yes, it is a slight surprise that I’m 90.”

He attributes these bonus decades to two younger men: his partner, the magazine journalist Rupert Thomas, 58, and the director Nicholas Hytner, 68, with whom he has worked on 11 theatre and screen projects. “It was luck that I met Rupert – over a shared taste in paintings, really – and also that I met Nick, more or less at the same time, around 30 years ago. It’s been the best period of my life. Without Rupert and Nick, I’d be nothing, I think.”