This action-adventure chronicles the escapades of a swashbuckling and brutal pirate, Captain Flint (Toby Stephens), his shipmates and his rivals in the early 18th-century Caribbean. The series is a prequel to Robert Louis Stevenson's "Treasure Island," and is set 20 years before the events depicted in that literary classic. While bounding the Spanish Main and jolly-rogering across the seas, Flint accepts a young recruit, John Silver (Luke Arnold), to join his crew, while later quashing a mutiny, questing for treasures, broadsiding other pirate vessels and exchanging fire with the ships of the British Navy who have been charged with blowing Flint out of the water.

Desperate to rid the Miramar Playa Hotel of Ben Diamond (Danny Huston), proprietor Ike Evans (Jeffrey Dean Morgan) attracts the attention of a Chicago crime boss (James Caan). Elsewhere, Ike's relationship with his two sons continues to deteriorate.