I guess this film can be seen as a railroad or train film as some of the reviewers of limited cognitive skills have already observed. And the film's not for anyone who dislikes foreign language films (unless you speak Russian). I love Russian films and this one did not disappoint one bit. But I almost passed on watching it due to some grossly shortsighted reviews left by a larger number of critics than I would have expected.
This unpretentious film is skilfully woven with fascinating period detail from post WW2 1940s Russian life. The well researched film demonstrates understanding and depth in its commentary on Politics and life under Stalin as well as everyday peasant life, the food, clothing, the unique colloquialisms (hopefully genuine) - all were a delight to take in, and I think most who give The Edge a chance will be pleasantly surprised.
Don't look for a complex or sophisticated plot in this film, although the human qualities demonstrated are as visceral and carnal as the large brown bear which appears several times. But the storyline easily hangs together and works quite well as the period vehicle for what it was intended.
Certainly anyone with an interest in trains and locomotives, engineering or physics will enjoy this film, but I feel sorry for the critic who is unable to appreciate the many other delights which the talented director Aleksey Uchitel has given us.