The World is under threat of destruction. As the politicians hedge their bets with atomic weapons, it seems no one is safe.

The only hope? A brilliant professor who knows how to make nations and people invulnerable to atomic attack. However, Professor Julian Conway has been kidnapped by power hungry men wishing to use his expertise for themselves.

Gordon Craigie assigns agent Peter Ross to get the Professor back: dead or alive. Ross is the secretive type; that had started from brooding in early boyhood, and the war had got rid of the brooding without dispensing with the secretiveness. He had always known what he wanted and set out to get it with a single-mindedness of purpose which Craigie often found necessary.

But Ross is in Love with two beautiful women – one of them is the Professor’s daughter and the other may just be the key to the whole mystery…

Dead or Alive is the 26th book in the Department Z series, and was originally published in 1951.