Secrets and rifts threaten the unity of the family, while those below stairs navigate social changes which put their futures in jeopardy.

Lady Mary's meddling gets Mr Carson into trouble with Mrs Hughes. Cora and Violet lock horns over the hospital takeover plans. Robert has a tough decision to make.

Period drama. Preparations for the wedding of Mr Carson and Mrs Hughes are under way. Edith meets up with an old acquaintance. Spratt has something to hide.

Period drama. As Tom and Sybbie settle back into life at Downton, the family and servants are surprised by the return of another old friend in unexpected circumstances.

Violet embroils the Minister of Health in the hospital row, but his visit ends in catastrophe. Mary's suspicions are aroused.

Period drama. Opinions are divided above and below stairs when Tom and Mary open Downton to the public for a day in aid of the hospital. Carson has an axe to grind with Thomas.

The family face a shocking turn of events at Brooklands race track, while Molesley and Daisy are put to the test.

A change of circumstance puts Bertie Pelham in the limelight, and Edith must decide whether to conceal her past at all costs or confront the truth and risk losing everything.

Romance abounds in the final episode of Downton Abbey, but for some the year's end is bitter-sweet.