"Charlie, think. How much do you know about your uncle?"

"Why, he's my mother's brother."

—from Shadow of a Doubt

Most uncles in movies, if they're any good at all, have no kids, and if they're really great, they're unmarried. Uncles as main characters are usually meant to illustrate alternatives—they let us glimpse what someone might have been like if he'd never had children, or they're gay, or they are simply a role model for a carefree bachelor future.

In the wonderful Mon Oncle, made in 1958, Jacques Tati takes up his recurring role as Monsieur Hulot, the good-natured bumbler of a Frenchman who's always just a little out of touch. It's the second Hulot movie, and this time around Hulot has a nephew. The kid, Gerard, is trapped in an ultramodern monster house, where there's nowhere to play, the kitchen cooks eggs by itself, and his mother only turns on the dribbling fish fountain for important guests. (Gerard's uncle doesn't seem to count.) For Gerard, his uncle is a representative of a traditional France that his house is trying to push into irrelevancy. The little boy vastly prefers to accompany his uncle to the old section of town, where there are lampposts that people run into, vendors who'll sell tasty food, and stray puppies galore. Gerard's uncle is infinitely superior to Gerard's harassed daddy, even if (or perhaps because) he never catches on to Gerard's pranks.

If Hulot is the good uncle, cheerful and incompetent, then Uncle Charlie in Hitchcock's 1943 film, Shadow of a Doubt, is his evil doppelgänger. Sexy, glamorous, and possessed of a secretly shriveled soul, Uncle Charlie (Joseph Cotten) is the namesake of his teenage niece (Teresa Wright) and her favorite person in the world. The creepiest thing about Hitchcock's most indelible villain is how slippery he is. At some moments, he and his niece Charlie are "sort of like twins"—they mimic each other's posture as they lie moodily in their beds on opposite coasts, and they seem to share a psychic link. At another point, when the girl is showing off to her friends on a promenade around town, the pair seems less like doubles and more like an incestuous couple. Soon enough we learn that if Uncle Charlie seems to like girls, he reviles "horrible, faded, fat, greedy women," and happily strangles them whenever their vanity gives him an opening. Your uncle may be a close friend, Shadow of a Doubt seems to say, but give him physical distance and a bit of leisure time, you can't really know what he'll get up to.

The movies teach us that uncles are mysterious. Uncle Charlie is unknowable, "just in business, you know, the way men are." And in Alain Resnais's 1980 behaviorist fable, Mon Oncle d'Amérique, the uncle doesn't exist except as a way to imagine an escape. There are caged rats, an island, and a textile factory, but there aren't any actual uncles. It's all very obscure.

annie@thestranger.com