Research biologist Piers Egerton has been working on a top-secret project for a number of years and has finally realised it is something he wants no part of. But the people he works for think he knows too much and he realises his life is in danger.
Lee Barber is a perfectly competent train driver, whose career is seemingly ruined through one simple error. Frustrated and desperate, the two strangers are thrown into each other's paths at a pivotal moment. Bound by the strange occurrence which has brought them together, Egerton and Barber must forge a tentative friendship if either of them is to get through this ordeal alive.
As Thames Valley Serious Crimes Squad, headed by Mike Yeadings, investigates the disappearance of one of the men, grim secrets of national importance emerge. Involvement spreads beyond the men's families to a mysterious immigrant couple with a tragic past. And suspicion falls on DS Zyczynski's journalist lover as he is drawn in to counter the threat to a young child's life.