Sam Youd was born in Lancashire in April 1922, during an unseasonable snowstorm.

As a boy, he was devoted to the newly emergent genre of science-fiction: 'In the early thirties,' he later wrote, 'we knew just enough about the solar system for its possibilities to be a magnet to the imagination.'

Over the following decades, his imagination flowed from science-fiction into general novels, cricket novels, medical novels, gothic romances, detective thrillers, light comedies ... In all he published fifty-six novels and a myriad of short stories, under his own name as well as eight different pen-names.

He is perhaps best known as John Christopher, author of the seminal work of speculative fiction, The Death of Grass. He wrote A Wrinkle in the Skin whilst living in Guernsey , and used the island as a significant element in the story. Shortly afterwards he started on The Tripods, the first of the stream of novels in the genre he pioneered, young adult dystopian fiction.

'I read somewhere,' Sam once said, 'that I have been cited as the greatest serial killer in fictional history, having destroyed civilisation in so many different ways - through famine, freezing, earthquakes, feral youth combined with religious fanaticism, and progeria.'

In an interview towards the end of his life, conversation turned to a recent spate of novels set on Mars and a possible setting for a John Christopher story: strand a group of people in a remote Martian enclave and see what happens.

The Mars aspect, he felt, was irrelevant. 'What happens between the people,' he said, 'that's the thing I'm interested in.'