From Wikipedia:
The Umbrellas of Cherbourg (French: Les Parapluies de Cherbourg) is a 1964 musical romantic drama film directed and written by Jacques Demy and starring Catherine Deneuve and Nino Castelnuovo. The music was composed by Michel Legrand. The film dialogue is all sung as recitative, including casual conversation, and is sung-through, or through-composed like some operas and stage musicals.
