In 17th century Holland, a faction of royalists is scheming to restore the monarchy and jail the De Witt brothers, who control the Republic. At the same time Tulip Fever is raging, and bulb-grower Cornelis van Baerle tries to obtain the secret of black tulips. Van Baerle will soon find himself threatened by radical royalists and rival bulb-grower Isaac van Boxtel.

A lieutenant saves an heiress from a wicked squire and is framed for murder.