“A dream of dark and troubling things” is the entire synopsis offered by David Lynch for his remarkable and wildly original first feature. The film relates the story of Henry, a hapless hero cursed with an unfortunate hairline, an innocence bordering on retardation, and a lonely life in a boxlike apartment he shares with his radiator. Things change quickly for Henry, however, when his girlfriend becomes pregnant (through means which neither of them can fathom). Best seen as a dark nightmare about sexuality, parenthood, and commitment in relationships, Eraserhead astounds through its expressionist sets and photography, its startling, sinister soundtrack, and its relentlessly imaginative fluency.