Goskino, the USSR State Committee for Cinematography, did not allow it to be shown at the Cannes Film Festival. The managing director of the festival, Maurice Bessy, was sympathetic to Tarkovsky. Upon hearing that Mirror would not be allowed to be shown in Cannes, he unsuccessfully threatened not to take any other Soviet film. See more
In the first scene, in which stutterer Yuri Zhary is being hypnotized, a shadow of the boom mic is prominently visible on the wall behind him. However, because this is clearly supposed to be a recreation of a TV broadcast, it appears to be a intentional error. See more
You know, I fell and found strange things here - roots, bushes... Has it ever occurred to you that plants can feel, know, even comprehend? The trees, this hazel-nut bush...
This is the alder-tree.
It doesn't matter. They don't run about. Like us who are rushing, fussing, uttering banalities. That's because we don't trust nature that is inside us. Always this suspiciousness, haste, and no time to stop and think.