The escort fell in on either side of the prisoners, and at a word of command the party moved forward. Down the corridor it marched, and through an open door into a grim-looking courtyard. Across this it proceeded, and came to a halt against a wall on the far side.-Biggles glanced at the sky. It was just turning pink with the first flush of dawn. 'If Ginger is going to do the rescue act, he hasn't got much time left.' He observed calmly.-Algy said nothing. His face was pale. In the uneasy atmosphere of Europe between the two World Wars, Biggles, Algy and Ginger are persuaded to defend a small middle European country from an aggressive neighbour backed up by an unnamed Big Power.