The Cold War's last secret wasn't a weapon. It was a question.

1983. The year the world came close to nuclear war twice.

An unexplained signal reaches three separate intelligence services. The evidence is the same. The interpretations are not.

• In Moscow, a senior KGB officer risks everything to stop what he has found from being buried.

• In London, an MI6 linguistics officer works to prevent a fatal misunderstanding.

• In Washington, a CIA analyst goes around his own agency to reach the one service that might listen.

Nobody sees the whole picture. Except you.

"A fascinating glimpse into the workings of intelligence agents with an ingenious speculative twist." — Kirkus Reviews

"Cold war tensions, conflicting intelligences, politics and international relations on a knife edge." — LoveReading (UK)

The signal is the news.

What governments do with it is the story.

What they fail to do with it is the warning.