The movie has some very effective moments. The visuals are very haunting and beautiful aided by an excellent score. However, the film has problems with pacing. It takes too long to get to its inevitable conclusion.
The acting is a bit ham fisted and stilted. Maximillian Schell is good in the film but the others are just ok.
The last ten minutes really deliver in terms of action and are exciting and thrilling but it is almost too late because we have had to watch a very slow moving story that wasted a lot of time.
I enjoyed the film despite its shortcomings. I can't really wholeheartedly recommend it unless you are watching it for nostalgia.