1943. World War II is raging across Europe and on the Pacific front. Kit Sutherland is hiding a huge secret when she is unexpectedly recruited to work as a young codebreaker at Arlington Hall, a US Signals Intelligence facility.

When Kit's roommate doesn't return home from a dance, it sparks a search that ends in a gruesome discovery. And soon it turns into a horrifying pattern: Government girls are being murdered in Washington, DC.

Kit joins forces with three other girl codebreakers, Dottie, Moya and Violet, and as they work to crack the killer's code, two things become terrifyingly clear: the murderer they're hunting is getting closer every moment ... and Kit's own secret could put her in more jeopardy than she ever imagined.

A young codebreaker at Arlington Hall - the secret WW2 Signals Intelligence unit in Washington DC - joins forces with other female codebreakers to hunt a vicious murderer who is killing US government girls. Another page-turning YA thriller from the author of None Shall Sleep, perfect for fans of A Good Girl's Guide to Murder.