The first three series, plus the Christmas special, of the ITV costume drama following the lives and loves of those above and below stairs in an English stately home.

In series one, set before the outbreak of World War One, the Grantham family, long time custodians of Downton Abbey, face a crisis when the heir to the estate dies on the Titanic. With his three daughters unable to inherit by law, Robert Crawley (Hugh Bonneville), the current Earl of Grantham, must try and marry his eldest daughter off in order to obtain an heir. Meanwhile, the family's determination to cling to class and rank is mirrored in a number of growing rivalries between the servants which threaten to undermine the smooth running of the house.

In series two, after the outbreak of WWI, Matthew (Dan Stevens) and Thomas (Rob James-Collier) are off fighting at the Somme, while both Lord Grantham and William (Thomas Howes) feel frustrated at being barred from taking part in the war. Meanwhile, Lady Sybil (Jessica Brown-Findlay) defies her aristocratic position and enlists in the Royal Army Nursing Corps and Lady Mary (Michelle Dockery) puts on a brave face when Matthew arrives home on leave with his future wife, Lavinia Swire (Zoe Boyle), in tow.

In series three, with the war finally over, the 1920s heralds the promise of a new age for those at Downton Abbey. But while the family prepare for the wedding of Lady Mary and Matthew, Lord Grantham learns that the future of Downton is in grave jeopardy after the collapse of investments made with his wife (Elizabeth McGovern)'s fortune. With the family beginning to gather for the wedding celebrations, a grand entrance by Cora's thoroughly modern mother, Martha Levinson (Shirley MacLaine), threatens to ruffle a few of the Dowager (Maggie Smith)'s feathers.