If ever a film demanded a tiny, tape-and-glue, “Doctor Who” budget, “The Hitchhiker’s Guide To The Galaxy” is it. The adaptation of Douglas Adams’ cult novel shows hints of the dry British humor that lit up the book, but most of it is drowned in the foaming whirlpool of special effects. The carefully layered tone—arid middle class Britons flying through space in a giant toaster-oven—is shattered again and again because the sheer magnitude of the production demands too much eye candy. It’s like the argument about the need to launch a nuclear missile strike: the huge expenditure of money is almost the only justification needed to use the things. The effects appear to be mere showing off, whereas Terry Gilliam, or even Tim Burton, would have used them more effectively as flourishes of whimsical and occasionally disturbing fantasy. The filmmakers were faithful to Adams in almost every respect but tone, and that flaw is fatal.

Still, there’s plenty of good material here. Martin Freeman’s middlebrow likability is put to good use, Mos Def shows off some decent comic sensibilities, and Marvin, voiced by Alan Rickman, is the most consistent laugh-getter. Sam Rockwell and Zoey Deschanel are both way too, well, American. Rockwell, as the Galactic President, puts in a game effort but his lounge lizard act seems out of place. Deschanel looks so bored, vacant, or flat-out stupid—the only range she demonstrates is that she could be any of the three—that she looks like her own wax simulacrum. Some of the effects make for undeniably witty jokes, such as the trip through the yarn dimension, or elaborate set pieces, like John Malkovich presiding over a flock of true believers in one of the movie’s Swiftian satirical stretches. In the end, the greatest tribute to Adams’ vision is the fact that the film manages to be just good enough for one to conclude that this is a decent adaptation of an unadaptable book.