A new second-in-command is appointed to Colditz, but Major Mohn – a distinguished and much decorated soldier is determined to continue fight the war inside Colditz and Simon Carter whose broken ankle is not mending is prepared to meet him head on, but a psychological battle between them has consequences for the Kommandant and Colonel Preston, who is forced to appoint a new escape officer.

A pair of caught French escapers bring back information that would greatly aid any escape attempt and Simon starts to devise a way of communicating with London – but it depends on his wife Cathy being able to understand a complicated code. At the same time a new prisoner – Page – seems to be a bit vague on facts and there is suspicion that he may not be all he appears to be.

The arrival of one of Britain's top fighter pilots - Squadron Leader Tony Shaw causes disagreements in the German staff as to how to handle such a specialist prisoner – but Shaw turns out to be more interested in studying English literature with fellow inmate James Porteous – however will Shaw settle down to a life of study while Simon Carter is badgering him to become the focal head of escapes?