Since 9/11, the door between the pilots and the passengers on an airliner must be locked and impossible to break down.

But what if the pilots are dead?

Tristie Merritt leads a renegade band of ex-soldiers. Their daring scam will take millions from a furious British government and give it to veterans' charities - if MI5 don't catch up with them first.

But faced with the ultimate terrorist outrage at 36,000 feet, MI5 and the CIA find that Merritt is their one hope of preventing global disaster.