Douglas Adams' cult mainstay The Hitchhiker's Guide to the Galaxy traveled a long, strange road from BBC radio show to book series to interactive CD-ROM to feature film, and die-hard fans will regret every scrap jettisoned along the way. Director Garth Jennings and screenwriter Karey Kirkpatrick, who revised the script Adams completed before his death in 2001, remain true to the material's shaggy, baggy spirit and successfully resist the temptation (or more likely pressure) to turn the movie into a gigantic CGI spectacle. Shortly before Earth is vaporized to make way for a hyperspace bypass, shabby little everyman Arthur Dent (Martin Freeman) is busy processing a series of life-altering revelations. First there's the news about Earth, then the fact that his friend, Ford Prefect (Mos Def), is actually an alien researching new material for the intergalactic best-seller "The Hitchhiker's Guide to the Galaxy," the bible of cosmic thumb-tripping. Veteran hitcher Ford gets them an illicit lift on one of the very ships that just destroyed Earth, and masterminds — if you can call it that — their escape from the awful Vogons, bureaucratic overlords of the universe. Ford and Arthur's next ride is aboard the Heart of Gold, which Ford's cousin, renegade Galactic President Zaphod Beeblebrox (Sam Rockwell), an insufferable dandy with two heads, three arms and half a brain, hijacked so he could search for the fabled planet Magrathea. The ancient Magratheans built a supercomputer (voiced by Helen Mirren) that spent 7.5 million years coming up with the answer that explains life, the universe and everything — it's 42 — and Zaphod hopes that by now it's come up with the question. His companions in questing are a desperately depressed android, Marvin (voiced by Alan Rickman), and Trillian, the girl (Zooey Deschanel) Arthur once tried to romance at a costume party but turned off with his boring, no-place-like-home attitude. The appeal of Adams' Hitchhiker books lies less in the narrative — though Dent's adventures are often quite amusing — than in the loopy digressions, a wildly imaginative mix of spacey science, navel-gazing noodling and a peculiarly English fatalism. Jennings opted to give the film an appealingly low-tech look and populated it with animatronic monsters designed by the Jim Henson Creature Shop and little Warwick Davis stoically shambling along inside the Marvin suit. Driven equally by big questions and the abiding desire for small pleasures, like a decent cup of tea, it's an eccentric, mind-bending head trip that greets every catastrophe with an endearingly goofy smile that embodies Hitchhiker's Guide's Zen mantra: Don't Panic!