Warning: wikipedia contains spoilers
The book is set in the 17th century in the region of Exmoor in Devon. John (or Jan) Ridd, a respectable farmer's son, becomes romantically involved with Lorna Doone, a member of the notorious Doone family, outlaws who live in an isolated valley. Lorna is destined to marry her cousin Carver Doone, but is in fact a foundling, originally the daughter of a nobleman, stolen away by the Doones. John eventually overcomes opposition to their marriage and defeats Carver Doone (who drowns in a swamp). Lorna is shot during their wedding ceremony, but survives, and the ending is a happy one. The historical background to the story includes the Battle of Sedgemoor.