A tale of obsession set in 1979 Santiago, Chile, follows an off-the-rails, impoverished and over-the-hill imitator of John Travolta’s character in “Saturday Night Fever,” who goes to any lengths to win a cash prize and recognition in a dance-like-Travolta TV contest. Meanwhile, tanks rumble through the city’s streets as Pinochet’s regime clamps down on anti-government activists, including the man’s dance group members.