An enemy's vengeance from the grave traps Mortimer out of time. Professor Mortimer is bequeathed an old house in France by a former adversary: Miloch, the evil genius of SOS Meteors fame. Along with the house is a letter inviting the Briton, as the only man of worthy intellect, to discover a fabulous invention left behind by the departed. Following recorded instructions, Mortimer activates the device ...and wakes up a hundred million years in the past! Thus begins an incredible odyssey through time...Captain Francis Blake, dashing head of England's MI5. Professor Philip Mortimer, world-renowned nuclear physicist. The most distinguished duo of gentleman-adventurers, battling the forces of evil and their arch nemesis Olrik around the globe, below the earth, even across time itself...The 19th adventure of Her Majesty's finest protectors!