Prime Minister Michael Callow faces a shocking dilemma when Princess Susannah, a much-loved member of the Royal Family, is kidnapped.

With danger at every turn, Diana and Matthew are forced to run. But will they escape in time? Series finale.

Diana’s aunts’ home gives up all sorts of secrets when Diana and Matthew pay a visit. Danger looms as Juliette breaks free from Gerbert.

Matthew and Baldwin race to save Diana from Satu’s dangerous dark magic. In Oxford, Sophie shocks Agatha with a confession.

Matthew crosses a dangerous line when he returns to Oxford. Diana discovers his dark past, before something unexpected tears them apart.

Diana gets a chilly welcome when she seeks safety at the Clairmont family home. Back in Oxford, trouble is brewing.

After traveling on the Blue Train from Calais to Nice, Hercule Poirot is pressed into service to help solve the murder of heiress Ruth Kettering who is found savagely beaten…

Camelot faces a new golden age, but even as the city flowers, the dark seeds of destruction are being sown. In the frozen wastelands of the north, men are disappearing…

Sherlock faces perhaps the most chilling enemy of his long career: the powerful and seemingly unassailable Culverton Smith – a man with a very dark secret indeed.

Sherlock waits to see where Moriarty will make his posthumous move. One mysterious case in particular baffles Scotland Yard – but Sherlock is more interested in a seemingly-trivial detail. Why…

A case of stolen letters leads Sherlock Holmes into a long conflict with Charles Augustus Magnussen, the Napoleon of blackmail, and the one man he truly hates. But how do…