LOS ANGELES: George Clayton Johnson, the legendary science-fiction writer who authored the first Star Trek television episode and several classic stories for the popular 1960s TV show The Twilight Zone, died on Christmas Day. He was 86.

Johnson, who also co-wrote the dark futuristic tale Logan’s Run, died of cancer in Los Angeles on December 25, his son, Paul B Johnson, told The Associated Press.

“Please emphasise how much he loved his fans, and judging by the overwhelming response I’ve received, from hundreds of people, known and unknown, he made quite an impact on them,” said his son, who has been deluged with calls, emails and social media postings in recent days.

Although not widely known outside of science-fiction circles, Johnson was revered among fans of the genre for his work, which also included collaborating with Ray Bradbury on the 1962, Oscar-nominated, animated short film Icarus Montgolfier Wright.

A popular figure at science-fiction conventions for decades, the soft-spoken but friendly author was instantly recognisable for his long, flowing white hair and beard, as well as what might best be described as his hippie attire.

Johnson’s best-known science-fiction work was likely Logan’s Run, co-written as a novel with William F Nolan in 1967 and released as a film in 1976. The dystopian story envisions a futuristic society in which young people live idyllic lives inside an enclosed dome but with one catch — they are executed when they turn 30.

Before Logan’s Run Johnson also created several of the best episodes of The Twilight Zone.

Johnson’s most prominent mainstream work was Ocean’s 11. In 1966, Johnson wrote The Man Trap, the premiere episode of Star Trek that introduced audiences to the crew of the USS Enterprise, including now familiar characters Capt James T Kirk and Mr Spock.

In addition to his son, Johnson is survived by a daughter, Judy Olive, and his wife, Lola Johnson.