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After a report on the Doomsday Weapon went missing from the Time Lords' files, a group of Time Lords in the Citadel on Gallifrey decided to send the Third Doctor to the planet Uxarieus to investigate. (TV: Colony in Space)

Some time later one of these Time Lords assisted in a control room during the crisis that required the help of the first three incarnations of the Doctor. (TV: The Three Doctors)