A miraculous blood offers immortality.

The subject made a good science fiction book. Now Kansas University professor James Gunn, who turned the idea into the 1962 science fiction novel “The Immortals,” is waiting for his brainchild to hit the big screen. But Gunn is learning that with Hollywood, it can be a long wait.

“You get philosophical about it,” the emeritus professor of English said. “You realize it’s really hard work to do anything along these lines.”

Gunn, a Kansas City, Mo., native, has authored nearly 100 stories and published numerous books, including “The Joy Makers” (1961) and “The Listeners” (1972).

It’s not easy to turn science fiction – a genre Gunn calls “a medium of ideas” – into movies. And when they do become feature films, it’s even harder for the films to resemble the written stories, Gunn said.

Kansas University professor James Gunn is waiting for his 1962 science fiction novel The

“The Immortals” first showed its screen potential in 1969, when it was turned into an ABC Movie of the Week.

It was later reworked into a short-lived television series.

In writing the original story, Gunn was interested in the way immortality would affect the world, but his idea was altered for the television versions. Instead, the TV focus was on the immortal himself and the attempts to chase him down and get his blood.

Gunn said he had a love-hate relationship with the alterations to his book. But he recognizes that science fiction films and novels are essentially two different media.

The science fiction film “tells you, in effect, don’t experiment, don’t take chances, don’t go far out, because if you do, you’ll unleash some hidden terrors that will destroy you and your family and maybe the whole world,” Gunn said.

But the written science fiction tale is generally more adventurous.

“It says: It isn’t what you do that is dangerous, but what you don’t know about the universe,” he said.

Some movies are true to the science fiction genre held sacred by its writers and readers, Gunn said. The 1936 “Things to Come” or the 1968 film “2001: A Space Odyssey” were right on or came pretty close, he said.

Warner Bros. now holds the option to the rights for “The Immortals.” The studio has paid about $90,000 to maintain its option.

As he works on his latest novel, Gunn holds on to hope that the movie version of “The Immortals” will be done, and maybe done well.

“It keeps life interesting,” he said of the waiting process. “Something good might happen.”