Officially, Max McLean doesn't exist.

An off-the-books assassin for the British government, he operates alone.

But when a routine hit goes badly wrong, a cryptic note on a $100 bill prised from his target's dead fingers suggests there's more to the mission than meets the eye.

Is someone from Max's former life trying to send him a message?

From Paris to Jerusalem and on to the frozen wastes of north-west Russia, Max is forced into a desperate race for the truth - with unknown enemies determined to stop him at any cost.

And when the secret coded into the banknote is finally revealed, only one thing is certain:

With the fate of the world in his possession, failure is not an option . . .