Written by Ashley Pharoah (Life on Mars, Ashes to Ashes), this two-part adaptation of the much-loved John Meade Falkner novel is set in the small Dorset village of Moonfleet. In the story, young John Trenchard (Aneurin Barnard - The White Queen) is desperate to join the local band of smugglers led by Elzevir Block (Ray Winstone - The Departed, Hugo). Together they embark on an adventure full of action, friendship, and humour, and hunt for a fabled lost diamond. Their journey takes them from 18th Century Dorset, to the jewellery quarter of The Hague, and on to a gripping, final sea voyage.

Sophie Cookson joins the cast as John's first love, Grace, who is also the daughter of Moonfleet's anti-smuggling magistrate, Mohune, played by Ben Chaplin (Mad Dogs, Dorian Gray). Omid Djalili (Gladiator) appears as a diamond merchant, Aldobrand, and Martin Trenaman (The Inbetweeners) as the Turnkey.