Then and Now, initially titled 54321 Countdown and then simply Countdown, was a series of prose features published in TV Century 21 throughout 1967, from issue 105 to 154.
Replacing the fifteen part Moonshot Apollo by David Stefan, the series was partly educational and compared various aspects of life in the 1960s to the magazine's shared universe of the 2060s. Articles usually focused on different technological advancements, but occasionally shined a light on subjects such as food or fashion.
One instalment of Then and Now crossed over with elements from the Doctor Who universe, namely Government from issue 147. The feature largely centred on the political division of 1967 in contrast to the world peace of 2067 which was achieved through the World Government. Consequently, the World Government capital of Unity City was referenced, a location originally introduced in The Daleks comic strip.