Downton Abbey--a sprawling Edwardian mansion and park nestled in the lush North Yorkshire countryside--needs an heir. A tragedy at sea has claimed the life of the presumed heir, and Lord Grantham is faced with the possibility that the house he's loved his whole life might one day belong to a distant cousin he's never met. Before he can worry about that, he must deal with his scandalous daughter, Lady Mary, who many believe to be the rightful heir...

Follows the lives of the aristocratic Crawley family and their servants in pre-WWI England and as they later face the challenges of war.