Where would we be without the Film Forum? It's a small place, tucked away on a lower Manhattan side street. But few theaters have such imagination, and derring-do, when it comes to introducing offbeat movies that might otherwise be overlooked.
Cases in point: the fascinating Soviet and West German pictures having their American theatrical premieres at the FF between now and the end of next month. Each is a winner that deserves to be picked up for widespread distribution.
Andrei Tarkovsky apparently wants to be the black sheep of Soviet film. He's a maverick who befuddles audiences and authorities alike, breaking the rules of common sense as readily as he ignores the conventions of recent Russian cinema.
His science-fiction epics, ''Solaris'' and ''The Stalker,'' are slow, insinuating, visually explosive journeys across a complicated web of memory, myth, and emotion. ''The Mirror,'' made in 1974 and also known as ''The Looking-Glass,'' pursues similar themes in autobiographical terms.
The plot, such as it is, deals with a man remembering his childhood while suffering a crisis in his adult life. We see long-ago events involving his mother - she pays a visit, talks with a neighbor, panics over a possible error in her work. In the present day, meanwhile, we see the man going through difficult moments with his own wife and child.
The incidents are developed at a leisurely pace, and connections between them are vague, as in a dream. Still more dreamlike are Tarkovsky's ecstatic flights into sheer hallucination, etched largely in billowing black-and-white images: hot-air balloons hovering in empty skies, a woman transformed into a surreal icon as she washes herself, a character floating in midair.
Such scenes are impossible to describe, so brilliantly imagined are they, and so organically woven into the rest of Tarkovsky's tapestry, which isn't half so engaging in its more mundane moments. I can only compare them to some creations of American filmmaker Bruce Conner, who has fashioned similar concoctions (though less delirious) out of old ''found footage'' remnants.
''The Mirror'' is a visionary work, successful only in part, blazingly eccentric even at its best. It lacks the sustained energy of Tarkovsky's science-fiction meditations. But at the many junctures where its forces mesh perfectly, it's an overwhelming experience.