As a child in Venezuela, Ariana Neumann is fascinated by the enigma of her father, who appears to be the epitome of success and strength, but who wakes at night screaming in a language she doesn't recognise. Then, one day, she finds an old identity document bearing his picture - but someone else's name. From a box of papers her father leaves for her when he dies, Ariana meticulously uncovers the extraordinary truth of his escape from Nazi-occupied Prague.

She follows him across Europe and reveals his astonishing choice to assume a fake identity and live out the war undercover, spying for the Allies in Berlin - deep in the 'darkest shadow'. Having known nothing of her father's past, not even that he was Jewish, Ariana's detective work also leads to the shocking discovery that a total of twenty-five members of the Neumann family were murdered by the Nazis.

Spanning nearly ninety years and crossing oceans, When Time Stopped is a powerful and beautifully wrought memoir in which Ariana comes to know the family that has been lost - and, ultimately, her own beloved father.