Gerry Anderson, the creator of hit TV shows including Thunderbirds, Stingray and Joe 90, has died at the age of 83.
Thunderbirds, a science-fiction fantasy about a daring rescue squad, ran from 1965 and was his most famous show.
Anderson had suffered from Alzheimer's since 2010 and the disease had worsened in recent months, his son Jamie said.
Jamie Anderson announced the news on his website, saying his father died peacefully in his sleep at noon on Wednesday.
"Gerry was diagnosed with mixed dementia two years ago and his condition worsened quite dramatically over the past six months," he wrote.
Gerry Anderson talked about the onset of the disease in June 2012.
His other creations included UFO, Space: 1999, Supercar and Fireball XL5.
Actor Brian Blessed, who worked with Anderson on shows including The Day After Tomorrow and Space 1999, told BBC News: "I think a light has gone out in the universe.
"He had a great sense of humour. He wasn't childish but child-like and he had a tremendous love of the universe and astronomy and scientists.
"He got their latest theories, which he would expand on. He was always galvanised and full of energy."