Thus Spoke Zarathustra. “Open the pod bay doors, Hal.” “I’m afraid, Dave.”

Fifty years after its release on April 3, 1968, Stanley Kubrick’s 2001: A Space Odyssey stands as a landmark achievement in motion picture history, having earned widespread respect and acclaim, with indelible moments that have entered the public consciousness. American Film Institute currently ranks it at #15 on its list of the 100 Greatest American Films of All Time, and #1 in the “Top 10 Sci-Fi” category. And yet, one of the film’s stars still feels it never got the full recognition—and the honor—it deserved.

“Planet of the Apes, which came out the same year, actually won an Academy Award for makeup for their apes, as opposed to the brilliance of the ape makeup in our film,” Keir Dullea recalls in an interview with SYFY WIRE. “If you look at them today, you can’t believe it.”

Dullea played David Bowman, mission commander aboard the U.S. spaceship Discovery, sent to Jupiter after a mysterious alien object, called a monolith, is discovered on Earth’s moon transmitting a powerful radio signal to the gas giant. Bowman is accompanied on the mission by his fellow astronaut, the ill-fated Frank Poole, who is played by Gary Lockwood. For both actors, the movie represented a singular chance to work with a director who was already hailed as a master.

“I knew that I’d been hired by one of the great filmmakers of the world,” Dullea says. “I was a huge Kubrick fan ever since I saw his first significantly important film, which I consider my favorite Kubrick film, Paths of Glory.”

Credit: Metro-Goldwyn-Mayer (MGM)

Dullea was cast without an audition, which amazes him to this day. “I’d never met Kubrick before getting hired,” he says. “And looking at my previous work — The Hoodlum Priest, David and Lisa — I don’t know how he got the idea from the characters I was portraying that I was right for the part. But I guess he had insights that I don’t have.”

Lockwood calls Kubrick “the smartest guy who ever picked up a viewfinder,” and says that he too was a huge admirer of the director’s work before being cast in 2001.

“I went to see The Killing when I was in college, and it was the first time I ever walked out of the theater and stopped to look at the poster, to see who directed it,” Lockwood tells SYFY WIRE. “Later on, I saw an ad in the newspaper for another Stanley Kubrick movie, and I went, ‘Stanley Kubrick? That’s the guy who made that other movie that I liked!’ I skipped football practice to see it—I lied to my coach, told him I had to go settle a traffic ticket. The movie was Paths of Glory. I watched it three times in a row.”

Both Dullea and Lockwood grew up reading science fiction. And before working on 2001, Lockwood had a role in what became another major Hollywood sci-fi project, having guest-starred as Lt. Commander Gary Mitchell in "Where No Man Has Gone Before,” the second pilot for Star Trek — the one that convinced NBC to greenlight the original TV series. (“Star Trek I did as a favor to [Gene] Roddenberry,” Lockwood says. “I couldn’t have cared less about it.”)

Upon reading the 2001 script, Dullea was pleasantly surprised to find it strikingly familiar to a story he had read more than a decade earlier, in a “Best Science Fiction of the Year” collection.

“When I read the opening of the script, it hit me — ‘The Sentinel,’ by Arthur C. Clarke, a short story in one of those volumes in the early 1950s,” Dullea explains.

He was correct. 2001 was based loosely on “The Sentinel,” as well as several other Arthur C. Clarke stories, with Clarke and Kubrick collaborating on the film’s screenplay. But according to Lockwood, one of the most memorable scenes in the movie was improvised on the set, at the suggestion of the actor himself.

“I came up with the idea of going into the pod where Bowman and Poole could discuss the various technical issues of disconnecting HAL [aka HAL 9000, the ship’s faulty computer and main operating system],” Lockwood says. He adds that a member of the film crew then suggested, “Why can’t HAL read your lips?” Lockwood says that everyone “just looked at each other like, ‘That’s it.’”

Credit: Metro-Goldwyn-Mayer (MGM)

Dullea says he was excited about the movie throughout production, but did not foresee what a visual experience it would become. “There was no way on the written page to give me a hint of the glorious images that ended up being in the film,” he says.

One of the people mainly responsible for those images was special effects wizard Douglas Trumbull, who was only 23 when he cold-called Kubrick for a job on the movie. By that time, Trumbull had already served as an illustrator and animator on To the Moon and Beyond, a 70 mm, 360-degree Cinerama film about spaceflight produced for the 1964 World’s Fair. The call paid off — he ended up working under Kubrick for the next two-and-a-half years. “He was my mentor, really, and 2001 was my film school,” Trumbull tells SYFY WIRE.

His first job on the movie was “typical animation — the computer-generated HAL readouts that were actually rear-projected 16 mm movies, using very traditional techniques,” says Trumbull. But the effects team soon realized they needed “like, 15,000 feet of animation, and it was going to take several years if we used traditional techniques.” Trumbull came up with a way to do it more quickly and less expensively. It involved the building of a new animation stand, through which the effects team would position a camera facing downward onto, as he describes it, “a kind of table under very controlled peg bars and alignment devices to make sure the artwork is repeatable and exactly in alignment.” Kubrick was impressed, and Trumbull’s stature on the film skyrocketed.

“I went from a lowly little animation guy to one of the leads in the entire effects department,” he says. Trumbull is credited in the film as Special Photographic Effects Supervisor. “I got into photography of miniatures and doing all the backgrounds and stars and planets.”

Trumbull was heavily involved in the filming of the “Stargate” sequence, in which Dullea’s Bowman, in a space pod, confronts a giant Monolith orbiting Jupiter and embarks on a transcendent journey through space and time. Working on that surreal, color-drenched sequence, Trumbull says, marked the beginning of his belief that “film could go way beyond what people were ordinarily doing with cameras and projectors.” He adds that it opened his mind to the idea that “something can actually move and change and be controlled while the shutter is open, to create some fourth-dimensional image that doesn’t exist in the real world. That was a big epiphany for me and for Kubrick.”

Trumbull describes the movie as “a big R&D effort. We were in completely uncharted waters — and that’s exactly where Kubrick wanted to be. He said, ‘We’re going to do something new and different, that no one’s ever seen before, and we’re going to figure out shot by shot how to get that.’ I loved it.”

Credit: Metro-Goldwyn-Mayer (MGM)

But Dullea, Lockwood, and Trumbull are all quick to note that despite its esteemed reputation today, 2001 got a mixed reception at best upon its original release.

“Some of the most well-known critics slammed the film like you would not believe,” Dullea recalls. “People did not know what to make of it. I remember Rock Hudson, at the West Coast premiere, got up and left in the middle muttering to himself, ‘What is this bull****?’”

“The only place where the movie was really well received was L.A.,” Lockwood says. “After we premiered 2001 in Hollywood, Warren Beatty came up to me — and Beatty is a very bright guy — and he said, ‘You’re lucky,’ and I knew just what he meant.” Lockwood adds, “I met the Beatles, they were neat guys, and John [Lennon] bought a ticket to every performance of 2001 for one year at Lester Square. He had a great mind, he was receptive to it.” (In fact, Lennon is quoted as having said, “2001? I see it every week.”)

“It’s a weird movie,” Trumbull acknowledges. “There are no over-the-shoulder shots, no reverses, there’s no typical melodrama, almost no suspense, and no character development. The movie got rebranded because nobody knew what the hell it was until they called it, ‘The Ultimate Trip,’ and then everybody smoked pot and sat in the front row, and that turned it around.”

Trumbull defends the story, calling it “epic, spectacular, and worthwhile—the whole notion of the transformation and evolution of the nature of human beings is what the movie was about.”

2001 may not have gotten an Oscar for makeup, but it did win one for Best Visual Effects, and its influence has been felt on science-fiction films ever since—particularly 1979’s Star Trek: The Motion Picture, on which Trumbull served as Special Photographic Effects Director. And of course, there was the underrated 1984 sequel, 2010, directed by Peter Hyams, in which Dullea, not looking a day older than he did in the original movie, reprised the role of David Bowman.

“It was a good gig,” Dullea says, “but it wasn’t 2001 — no film is 2001.”

Credit: Metro-Goldwyn-Mayer (MGM)

THE ODYSSEY OF 2001

For Dullea, Lockwood, and Trumbull, 2001: A Space Odyssey has never really gone away. They’ve each attended many screenings and retrospectives over the years. (“I’ve seen 2001 so many times I can’t bear it anymore,” Lockwood jokes.) Dullea recently worked with Turner Classic Movies on an animated short based on a 1968 Playboy interview with Stanley Kubrick. Dullea provides Kubrick’s voice, and describes the interview as “beyond brilliant,” revealing the director as “not only a film genius, but also an extraordinary philosopher.”

Lockwood is completing his autobiography, which has a 2001-inspired working title: Beyond the Pod Bay Doors: The Adventures of an Actor-Cowboy-Surfer Dude. “A lot of it is bar fights, women, fast cars, surfing, and crazy stories about people I knew, including Elvis,” he explains.

Trumbull, who says that he has always strived to improve upon his work on 2001, has developed Magi, a new 3D filmmaking process to significantly upgrade digital photography and projection. It operates at 120 frames per second, rather than the standard 24 fps, making the picture quality “absolutely spectacular and vivid,” to deliver an “immersive experience to bring audiences back to movie theaters.” He is working to show filmmakers, studios, and exhibitors how it can lead to “a rebirth of the movie industry.”

But Trumbull still takes great satisfaction in his work on 2001. “It’s one of the few movies that’s withstood the test of time,” he says. “I’m really proud of it.”

As are its two lead actors.

“It may be the most impressive movie ever made,” Lockwood says. “It’s silly, absurd, to ask if it still holds up. It will never not hold up — have you seen anything better? I haven’t.”

“I think it’s the Citizen Kane of our era,” Dullea says. “I’m a very lucky man to be a key element in this film. I knew at the time, because I was working with this extraordinary director, that it was going to be thought of as an important film — but I don’t think I could have dreamed that 50 years later, I’d be having this kind of discussion.”