Enemy spies in London.

Fugitives in the South American jungle.

One man connecting them...

MI5 officer Jonas Merrick has spent a lifetime within the shadows of the secret service. But intelligence of a Russian sleeper network operating in the heart of London presents a threat unlike any he has encountered before.

Thousands of miles away, in Paraguay, two lost souls from Jonas' past are on the run. Alongside the local militia, they make haste for the Brazilian border, pursued through hostile terrain by agents who will not stop until they capture them: dead or alive.

As events unfold across continents, with British security at dire risk, a dogged and deadly pursuit closing in, Jonas Merrick might be the only man capable of averting the inevitable . . .