You need to watch the most underrated sci-fi blockbuster on HBO Max ASAP

It’s hard to imagine a better endorsement for any young comedy writer fresh out of college than the confidence of Monty Python.

But after the troupe’s Graham Chapman discovered Douglas Adams at a revue of his university’s comedy group, Adams soon earned writing credits on Month Python’s Flying Circus, even making brief cameos in the massively popular sketch-comedy series.

But this work, however exciting, wasn’t getting Adams where he wanted to go. “I kept trying to sell the idea of a science-fiction comedy, but no one was interested,” the author told science fiction magazine Darker Matter in 1979. Adams eventually found work with the long-running British sci-fi series Doctor Who, but the limitations of this family-friendly series left the writer, who had grown up idolizing Kurt Vonnegut, unsatisfied. Adams decided he needed to create his own sci-fi sandbox to play in.

“I thought ‘What would I really like to hear?’” Adams recalled to Darker Matter. “‘What would excite me?’” The answer came to him while he was backpacking in Austria, drunk in a field. It turned out to be a radio play called The Hitchhiker’s Guide to the Galaxy. The rest, as they say, is history.

By the time Gareth Jennings delivered a blockbuster movie adaptation of Adams’ best-known creation in 2005 (currently streaming on HBO Max), Hitchhiker’s Guide had appeared in just about every other format. The radio play was a smash hit, which led to Adams putting out a condensed version of his sci-fi yarn on vinyl, as well as book adaptations of his work.

The Hitchhiker’s Guide to the Galaxy books took on a life of their own, selling millions of copies and eventually spawning computer games, comic books, a stage play, a website called H2G2, and a TV series. Adams spent years trying to get a movie made and dealing with rejections from major studios, but when Star Wars made it clear such a project could be financially lucrative, he actually cooled on the idea.

Why? Adams was cautious about the idea of condensing his sprawling universe into “Star Wars with jokes,” as he put it. Even when he felt he had the right partners, as when Bill Murray or Dan Aykroyd were both considering playing alien researcher Ford Prefect, those partners would vanish (in the case of those two stars, they opted to make Ghostbusters instead). Adams eventually moved on to other projects, but the idea stayed with him. He died in 2001, having only recently submitted one last draft of a screenplay.

Robbie Stamp, a longtime friend of Adams and executive producer on the movie, told Slashdot at its 2005 premiere that he decided “to stay with making the movie after Douglas died because I knew just how desperately Douglas wanted” the work on the big screen. With some help from Austin Powers director and eventual producer Jay Roach, it finally happened.

Bringing Adams’ vision to life were modern actors: Sherlock’s Martin Freeman (then best-known for The Office) as the quintessentially British Arthur Dent; Zooey Deschanel as Trillian, the human survivor who once ditched Arthur at a party; Sam Rockwell as Zaphod Beeblebrox, the hedonistic, two-headed President of Universe; and Mos Def as Ford Prefect.

By the point production moved forward, the books had become so embedded within British culture that there were worries an American cast would turn the work into what Adams had feared all along. There were specific fears about casting Mos Def. “He's not going to be playing a hip-hop Ford is he?” H2G2 asked Jennings about the rapper, once known as a child actor.

Even aside from the cringe-worthy racism of such questions, there was no need to worry. Working off Adams’ script with some structural rewrites, the movie faithfully captures the author’s zany and neurotic attitude, starting with an opening musical number from dolphins fleeing Earth.

From there, the film moves along to Freeman’s Arthur Dent protesting the demolition of his home and Mos Def’s Ford Prefect hurriedly worrying him about the destruction of his larger home: the Earth. Then, the “bad-tempered, bureaucratic, officious and callous” (although not actually evil) Vogons destroy the entire planet — for reasons that are very similar to those reasons Arthur’s house was being demolished. Ford is able to save Arthur; after getting kicked off of the Vogon ship, the two find themselves, however improbably, on the stolen ship of Zaphod Beeblebrox (Rockwell) and Trillian (Deschanel).

Just as Adams realized that radio plays and books were very different, he knew that a movie was entirely its own beast. Adding the manipulative religious leader Humma Kavula (played with a creepy cool by John Malkovich) into his script supplies some extra tension, a love story between Arthur and Trillian works because of Freeman and Deschanel’s chemistry, and the mysterious paddles that slap anyone with an idea on Vogsphere feel like they’re right out of a Monty Python sketch.

Hitchhiker’s Guide also feels like a very mid-Aughts movie, and that’s not just because of a post-Elf Deschanel. It doles out its cynicism and wonders in equal quantities, not as crassly as Spaceballs though maybe wrapping it all up a little too neatly.

But the movie’s cast fights hard to make the movie weird, from the hyperactive Mos Def to a perpetually depressed Alan Rickman voicing the android Marvin (portrayed physically by Warwick Davis), to Bill Nighy as nervous planet builder Slartibartfast. Helen Mirren co-stars as a bored supercomputer and Stephen Fry is the trustworthy Guide.

While the movie was a financial success, it wasn’t the type of super-hit that earned sequel after sequel. So Hitchhiker’s Guide stands alone, waiting for another generation to discover its endless world and offering them only one piece of advice: don’t panic.

The Hitchhiker’s Guide to the Galaxy is now streaming on HBO Max.