Putting aside her gnawing doubts, Margaret (Claire Foy) continues with her plan to secure her claim to Inveraray Castle. With Ian (Paul Bettany) increasingly reluctant to leave the isolation of the Highlands, Margaret is starting to miss the whirlwind of London society.

Tensions between the couple threaten to finally boil over when the cost of raising the treasure grows ever higher, and Ian shows zero sign of giving up. Ignoring her husband’s demands, and with her father’s attention now on his new, much younger wife, Margaret finds solace in partying the night away with a new partner in crime. And a love affair or two can’t hurt either.

When the money finally runs out and other influences seem to conspire against her, Margaret has just one last chance, she thinks, to save her marriage. But what Margaret doesn’t realise is that a small, intimate photograph, tucked safely away in her London townhouse, has the potential to destroy everything she’s ever worked for - and haunt her for the rest of her life.

A Very British Scandal is made by Blueprint Pictures for BBC One and BBC iPlayer.