Notable for its technical proficiency, its authentic Russian underworld setting, and its thoughtful if underdeveloped handicapper-rights subtext, Mute Witness is, underneath it all, a fairly standard-issue thriller. Nevertheless, Anthony Waller's effective direction and Marina Zudina's involving lead performance keep the film watchable even when too many hoary red herrings accumulate and the screenplay lapses into cartoony violence. Several effective chase sequences, including one set in an elevator shaft, lend a degree of novelty to the suspense-film trappings. Wilbert Hirsch's music is fairly dreadful, but most everything else is better than average -- especially the sets, which effectively portray the social microcosms of both a movie shoot and an apartment building. More important than any of the film's technical accomplishments, however, is its facility with varied and effective moods. A good deal of character-driven humor offsets the sense of rising dread, but once the thrills start, they're pretty, well, thrilling.