During the Second World War messages were decoded by the celebrated code-breaking people at Bletchley Park. Before the messages could be decoded they had to be collected. Thousands of young men and women went wherever the war went to locate and monitore endless streams of radio traffic around the clock. They transcribed its Morse code and sent it on to be decoded. The people that gathered the messages were part of the Y or Wireless Service. The secret listeners hidden story and vital contribution to the war effort can be told at last.

1. Tuning in to the enemy -- 2. Reporting for special duties -- 3. The human computers -- 4. The listeners at large -- 5. The Blitz and the ghost voices -- 6. Heat, sand and ashes -- 7. A world wide web of intelligence -- 8. Feuds, farce and panic -- 9. Wilder shores and secret missions -- 10. This is no holiday camp -- 11. Storms in the desert -- 12. Rommel and the art of dirty tricks -- 13. No so quiet on the domestic front -- 14. Life-long friendships were forged -- 15. By the sleepy lagoon -- 16. Foreboding and frustration -- 17. Witnesses to different worlds -- 18. D-Day and after -- 19. The end and the beginning -- 20. The legacy of the listeners.