The discovery of the leak leads the resistance to abandon contact with Penny yet again, as the German security services are clearly aware of his participation in the resistance and hope by monitoring him they can discover the identity of other members. Penny is therefore surprised when Kennedy suddenly contacts him in July with a new mission: to smuggle out Otto Frisch, who the "Gestapo" has discovered knows information which could be vital to the development of a "superbomb". Travelling to Liverpool, they succeed in persuading Frisch to agree to escape. Avoiding discovery, Penny hides Frisch among the Jenner family, where he poses as a visiting relative. The Germans order a second round-up of the Jews, though, this time including native-born British citizens. Frisch is captured along with the Jenners, and Penny and Cordington travel to Imber in order to stage an escape from the concentration camp the Germans have built there.