The story concerns a small team of geologists -- two college students, a mentor and a guide -- prospecting for industrial diamonds in Siberia. Theirs is a patriotic mission; should they succeed, they'll reduce the USSR's dependence on imported diamonds. But prospectors have been hunting for diamonds for years with no luck, and our team does no better at first. Our point-of-view character is Konstantin, the author of the titular unsent letter addressed to his beloved Vera, whom we see in his reveries. For a while, I wondered whether Vera was actually dead and that was why the letter goes unsent, but whether she's alive or not soon becomes a secondary matter.
Suffice it to say that the two young geologists and lovers, Vera and Andrei, make the big discovery shortly after Vera fends off unwanted advances from the guide Sergei. They hardly have time to announce their find via radio before a forest fire separates them from most of their supplies. After their radio fails, they're stranded in the taiga with winter coming fast. The government tries to reach them, but there's a lot of territory to cover, and as they search in vain the party dwindles to a final survivor floating downriver on a makeshift frozen raft....
I haven't seen the other Kalatozov films but I know his reputation for daredevil camerawork, particularly in I Am Cuba. Letter Never Sent lives up to that reputation. Kalatozov was a director who worked in three dimensions without special technology apart from a mobile camera and an awareness of the space outside the camera frame. He likes to swing the camera left or right to catch important details or simply to follow action outside the original frame, broadening our perspective of the landscape while doing so. Sometimes he just lets the camera run and run in tracking shots or POV shots that anticipate the camerawork in Sam Raimi's Evil Dead movies. The persistent effect of this film is the reminder that the taiga is bigger and more dangerous than we first realize. But Kalatozov goes beyond that. He illustrates the fervent effort of the expedition by superimposing fire over montages of the team in motion or in action. At times the movement of the camera and the movements of the people and the elements make the frame an utterly abstract blur, as Nikolay Kryukov's Shostakovichite music churns away to underscore the symbolic industriousness of it all. It's definitely the opposite of Socialist Realism, and you don't have to be a Stalinist commissar to find it somewhat self-indulgent while admiring the visual ambition behind it.
Kalatozov settles down to more naturalistic filmmaking as the struggle for survival takes over the story, though he throws in one abstract attempt to illustrate the dimming of consciousness at the moment of death. In its second half Letter Never Sent transforms from nature adventure with a hint of romance and pathos to a grimly inspiring tale of heroic sacrifice. While our heroes have informed the government of their find, they still need to deliver a map of the diamond field's exact location. They can do without anything else, but someone has to get that map to civilization. The nearest the picture comes to Communist propaganda is its validation of sacrifice for the motherland. Its most mawkish moment comes when Konstantin reminds Vera of her Young Pioneer oath and observes that most people who memorize it never really have to live up to it, but now's the time. Whether you interpret the ending as happy or not, the message seems to be that it was all worth doing, whatever the cost. Whether you agree probably depends less on your opinion of the historical phenomenon of Marxist-Leninism than on whether such a mission, no matter for whose sake, is worth such sacrifice. The Soviets must have thought it was worth it, and that Kalatozov thought so, because the film was released rather than shelved. The impression it leaves today is of camerawork as an end unto itself and characters as expendable as actual people were once presumed to be under Communism. The artistic self-indulgence of Letter Never Sent somewhat subverts its evocation of nature's extremes, but as an exercise in sheer cinematic artistry it's an interesting addition to the Soviet cinema canon.