The year is 1800, and Britain and France have been at war since 1798, in what later was to be known as the War of the Second Coalition. Gilliatt, a fisherman-turned-smuggler on Guernsey, agrees to transport a beautiful woman, Drouchette, to the French coast on his ship the "Sea Devil". Drouchette tells him that she intends to organise the rescue of her brother from a French prison. Gilliatt finds himself falling in love and so feels betrayed when he later learns that Drouchette is a countess helping Napoleon plan an invasion of Great Britain. However, in reality she is a British agent working to thwart this invasion. Not knowing this, and believing her a French spy, Gilliat kidnaps her and takes her back to Guernsey. He takes her to Lethiery and accuses her of being a French spy. However Lethiery had organised the whole thing so instead of imprisoning her he returns her to France.