The fortunes of war are turning. The Nazi forces are in retreat. Hitler has ordered immediate deployment of the Luftwaffe's hi-tech, war- winning, airborne weapon system The Focke Wolf FW-600 Kobra.

Two young boys are murdered for what they have seen. An SOE field agent's radio message is suddenly terminated after he makes a terrifying discovery at a secret underground factory in Bavaria.

When Prime Minister Winston Churchill orders the threat to be neutralised, Sarah Porter, a ferry pilot of the Air Transport Auxiliary and John Messenger, a wounded fighter pilot are thrust together in what amounts to be a potentially suicidal mission.

Timing is essential if they are to complete the mission and stay alive. But nothing ever works to plan; and when capture, torture, sexual torment, injury and death are thrown into the melting pot, anything could happen.

And it does...