Julia is a switchboard operator in Mexico City who divides her time between her job, her daughter and Danzon. Every Wednesday Julia dances Danzon with Carmelo in the old ballroom "Salon Colonia". They've danced for years but barely know each other. One night Carmelo disappears without a trace. Feeling lonely and sad, Julia takes a train to Veracruz, where she knows Carmelo has a brother.
