Somebody's interfering with time. The Doctor, Rose and Captain Jack arrive on modern-day Earth to find the culprit and discover a Neanderthal Man, twenty-eight thousand years after his race became extinct. Only a trip back to the primeval dawn of humanity can solve the mystery. Who are the mysterious humans from the distant future now living in that distant past? What hideous monsters are trying to escape from behind the Grey Door? Is Rose going to end up married to a caveman? Caught between three very different types of human being past, present and future the Doctor, Rose and Captain Jack must learn the truth behind the Osterberg experiment before the monstrous Hy-Bractors escape to change humanity's history forever. Featuring the Doctor, Rose and Captain Jack as played by Christopher Eccleston, Billie Piper and John Barrowman in the hit series from BBC Television.

加雷斯·羅伯茨（英），生於1968年6月5日，畢業於溫徹斯特大學戲劇係，是英國著名的編劇和小說傢。曾操刀科幻劇《神秘博士》和《莎拉·簡大冒險》等多部英國長壽劇集的編劇工作，也是《神秘博士》官方小說的禦用作傢之一。