The film is a historical drama set during the reign of Elizabeth I (Flora Robson), focusing on the English defeat of the Spanish Armada, whence the title. In 1588, relations between Spain and England are at the breaking point. With the support of Queen Elizabeth I, British sea raiders such as Sir Francis Drake regularly capture Spanish merchantmen bringing gold from the New World.
If anyone ever doubted the kind of actor Laurence Olivier was going to become, then they need only watch this and it is as plain as the nose on his handsome young face. Here, though, his over-acting (and singing) in the role of the enthusiastic "Michael Ingleby" rather badly dates an otherwise quite entertaining recounting of the machinations leading up build up to the Spanish Armada's attempt to invade Elizabethan England. Flora Robson always did carry off the role of a monarch well and Morton Selten (reputedly a child of Edward VII), Vivien Leigh, Raymond Massey and a slightly camp Leslie Banks serve well in support as this story of court intrigues and romance unfolds. Though it is mostly stage bound there are a few attempts to take it outside, the costumes look the part and it's quite menacingly scored at times, too. Keep a look out for early appearances by James Mason and Robert Newton and remember - a Spanish lady may retire, but she never goes to bed!