It is a fact-based drama depicting the 1963 divorce of the Duke and Duchess of Argyll.
The Radio Times described it as “one of the most extraordinary and brutal legal cases of the 20th century, notorious for scandalous accusations and salacious photographs”.
Margaret and Ian first meet when he is still married and she is in the final stages of a divorce.
They eventually marry and begin work on reopening his ancestral castle – a task that leads to massive debts and rising tensions.
When will BBC A Very British Scandal be on TV?
A Very British Scandal will first air at 9pm on Boxing Day on BBC One.
The remaining two episodes will be shown at the same time on the same channel in the proceeding two days.
BBC A Very British Scandal full cast
Claire Foy as Margaret Campbell
Paul Bettany as Ian Campbell
Julia Davis as Maureen, Marchioness of Dufferin
Phoebe Nicholls as Helen Mann Hannay
Richard McCabe as George Whigham
Camilla Rutherford as Diana Napier Wolkowicki
Sophie Ward as Janet
Amanda Drew as Yvonne McPherson
Oliver Chris as George Emslie QC