When an aging ex-IRA man is found dead, a Garda inspector suspects the involvement of his old comrade, now a powerful politician and industrialist. But pursuing the case is likely to have consequences for both the policeman and his family.

The Master, in the guise of Professor Thascalos, has constructed at the Newton Institute in Wootton a device known as TOMTIT - Transmission Of Matter Through Interstitial Time - to gain control over Kronos, a creature from outside time. The creature is summoned but proves to be uncontrollable.

A secret, high-technology international agency called SHADO defends Earth from alien invaders.

The adventures of The Doctor, a time-traveling humanoid alien known as a Time Lord. He explores the universe in his TARDIS, a sentient time-traveling spaceship. Its exterior appears as a blue British police box, which was a common sight in Britain in 1963 when the series first aired. Along with a succession of companions, The Doctor faces a variety of foes while working to save civilizations, help ordinary people, and right many wrongs.