The bomb blast causes many casualties and, as martial law is imposed. Douglas forges papers to take his son to the safety of the unoccupied zone with his neighbour Joyce Sheenan. Returning to work he discovers that Harry has been arrested as a Resistance member but is able to secure his release. Barbara reintroduces him to Sir Robert Benson's group where he learns they are planning to join with the German army in blowing up the bomb factory and freeing the king but need his cooperation. Having sheltered Sylvia after she has escaped from the detention camp he is called to another murder scene, the victim this time being Bernard Staines, a member of Benson's covert Resistance party. Before he can fulfill his obligation he is told that Barbara has been taken by the Germans.