Searching for the third segment to the Key to Time brings the Doctor and Romana to present-day Earth, where the travellers have to contend with stone circles, Druidic rituals and a not-so-mythical goddess known as the Cailleach.
1961
2021
1963
1962
1995
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1976
2010
2011
1915
1978
1990
2024
1993