It is 1588 and King Philip of Spain has assembled the greatest fleet and the most powerful army in the world. It is envisaged that the Armada, commanded by the brave and chivalric Duke of Medina Sidonia, will crush the English and bring an end to the reign of Queen Elizabeth.

One man who has inside knowledge of this event is the young Henry Gresham. Caught up in the intrigues of Elizabeth's court as its inhabitants jostle for power and favour, he begins to realise that are many there who resent his youth, wealth and good looks. His position as a spy for Walsingham further endangers his life - and when he finds himself sailing on the Armada during his mission to spy on Sir Francis Drake, who is deemed suspicious of siding with the Spanish, he's not entirely certain where the real threat lies...