OK, OK, strictly speaking it isn't Marvin's movie; try not to be so picky. The Hitchhiker's Guide to the Galaxy movie was released on April 29, 2005.
Marvin didn't enjoy it; it gave him a headache.
The book The Making of The Hitchhiker's Guide to the Galaxy, 2005 (edited by Robbie Stamp, ISBN 0 752225855) includes a production still (41 kBytes) showing Marvin with an actor who played a cameo role in the film.
The movie has three websites: