A marriage built on lies, a man with many faces, an unpaid debt to the secret service - rich drama from the author of The Infatuations.

'For a while, she wasn't sure that her husband was her husband. Sometimes she thought he was, and sometimes not.'

Berta and Tomás meet in Madrid and, though both young, they decide to spend their lives together. Eighteen and betrothed, Tomás leaves to study at Oxford. His talent for languages quickly catches the interest of a certain government agency, but Tomás resists their offers - until one day he makes a mistake that will affect the rest of his life, and that of his beloved Berta. After university he returns to marry her, knowing he won't be able to stay for long . . .

Gripping and intricate, Berta Isla is about a relationship built on secrets and lies - and the equal forces of resentment and loyalty at its core.