When the Siren enters in the second scene — its sole female — she’s immediately spectacular. She runs in on point, in profile, crowned with a long purple cloak trailing behind her (see below). She’s unlike any other creature in ballet.
She announces herself with big flourishes of each leg, and ritualistic windings of her cloak about her shoulders and thighs. Everything she does amazes — the flamboyant way she parts and extends those legs! — perhaps nowhere more than when she marches on all fours (hands and points), her chest and pelvis facing the sky, with that royal cloak trailing from her neck and her thighs slicing up into the air: right, left, right. The Prodigal, as the dance world calls him, stares at her as if she’s from outer space.

“Prodigal” returns this week to American Ballet Theater repertory, with two casts; in January it returns to New York City Ballet for five performances, Jan. 17 to 29. Even if you know the 1920s silent-movie vamps made famous by Garbo and her predecessors, this Siren is a singular sensation. She flourishes her hands ceremoniously in the air, and she has a gesture where one hand slowly rises behind her crown like the fan of a cobra’s hood. (In an earlier and yet deadlier version, the hand stayed closed and pointing upward, in the shape of a snake’s head.)

When she dances with the hero, she seems to tower over him, and to take possession of him in what remains one of the most overtly sexual pas de deux ever made in ballet. She pins his pelvis to hers with one raised leg, and she clasps his head to her breast in a way that suggests she’s also the mother he’s been missing. She’s a femme fatale all right; she’s voluptuous, glamorous, but Balanchine also made her to be cold, snakelike, lethal and brutal.