In the quiet cul-de-sac where Keith and Stephen live there is very little evidence of the Second World War.

But the two friends suspect that the inhabitants of the Close are not what they seem.

As Keith authoritatively informs the trusting Stephen, the whole district is riddled with secret passages and underground laboratories - hideaways for any number of murderers, unsung war heroes and secret agents.

Then one day Keith announces an even more disconcerting discovery: the Germans have infiltrated his own family. And when the secret underground world they have postulated emerges from the shadows they find themselves engulfed in mysteries far deeper and more painful than they had bargained for.

In this beautiful new novel Michael Frayn evokes a time and characters which are as vivid now as if they had appeared before us today.