The Flashing Blade (Le Chevalier Tempête) is a French television serial made in the late 1960s, which was broadcast in the UK on BBC children's television during the 1960s, with several re-runs in the 1970s. Dubbed from French into English, the action was set in 17th century France, during a period of war between France and Spain. The plot involves a besieged French garrison in a castle (Fort Casal) on the Savoie border, and the efforts of a dashing spy to engineer their rescue.