"I don't believe in fiction," says Andrei Tarkovsky, in answer to a question about his use of science fiction stories in two of his films, Solaris and Stalker.
You could see this documentary as an elaboration of Tarkovsky's idea of fiction and truth -- which he usually characterizes as "poetic". It's a documentary that looks and sounds just like a Tarkovsky film, and I think Tarkovsky would probably not have felt that there was any essential difference in truthfulness between this and any of his other films. Whatever his intention in making it, it is fascinating as a meditation on the nature of truth and representation.
At first I thought it must have been staged to some degree, but over the course of the film it becomes obvious that it was not. This mixture of an almost cinema verite quality with the look and feel of a Tarkovsky film seems surprisingly natural, and this is what makes this film so interesting. At one point, asked what advice he would give to aspiring filmmakers, Tarkovsky says that filmmakers should not separate their films from their lives. And in Tarkovsky's manner, the way he talks and the gestures he makes, the brooding way he answers questions, propping himself against a window grate as if to shut himself off from the world for a minute, fiddling with a blade of grass, in all of it you can clearly see that everywhere his characters and the style of his films does indeed come authentically from him, from his life as he sees it. And so it is with this documentary, which brings his life and his aesthetic together in such a fascinating way.
Although Voyage In Time was obviously shot on a small budget with unimpressive equipment (it's interesting to see Tarkovsky's languid style executed with the jittery camera motions of an inferior tripod), it is another Tarkovsky film through and through, and deserves to be considered among his body of work rather than as an adjunct.