Deathwatch

Finding a killer in the middle of a blitz is murder.
When a cryptanalyst in Britain's top secret Code and Cypher School is murdered, alarms sound in the highest echelons of Parliament. Was it merely a lover's quarrel that ended her life, or was she killed after telling the Germans everything they wanted to know? That's what MI6 Agent, Commander Grey Hamilton must find out.
He is joined in the chase by an old university friend from Scotland Yard, and a young American genius who has been singled out by the killer as his next victim.
As the Luftwaffe escalates its reign of terror over London, the unlikely team dodges bombs while searching the Underground and London docks knowing failure is not an option. The lives of English soldiers and perhaps the fate of the British Empire itself, is at stake.