The Doctor and Romana arrive on scene where they meet Professor Amelia Rumford and her assistant Vivien Fay, who are working around the stone circle. When the Doctor discovers a spaceship hovering over the circle, his life is jeopardized.

The Doctor and Romana visit the Leisure Hive on the planet Argolis following a nuclear war.

The Doctor is invited to visit the planet Tigella by its leader, Zastor, who has become concerned about disputes between his people's two opposing factions, the religious Deons and the scientist Savants. The TARDIS is intercepted by the megalomaniacal xerophyte Meglos, last survivor of the planet Zolfa-Thura, and trapped in a chronic hysteresis - a time loop - but the Doctor and Romana manage to free it.

Guards await Russian commandos.

A Viking curse nears fulfillment.

The Doctor, Amy and Rory arrive in a future Earth; the Doctor must prevent civil war when doppelgangers are liberated from their human originals.

Time-traveler plans to ensure Harold's victory at Battle of Hastings.

The human race rejoices as ghosts of loved ones return home; an invasion force threatens modern day Earth.

Smith and Jones are under siege.

The TARDIS lands aboard an ark bound for a 700-year journey to a new planet.