I thought this was a hysterical movie. I haven't laughed that hard in a LONG time. I thought the movie stayed reasonably true to the book, though it's kind of hard to tell. (What with the way the book twists and turns it's way through the story) Marvin was perfect. They did Zaphod a little differently than I was expecting, and I don't remember him ever losing his second head, but it's been awhile since I've read the books. If you are a fan of the books, this movie is a must see!!!