On the way to Heathrow Airport for her first day as an air stewardess, Tegan's car gets a puncture. Entering a nearby Police Box, she's transported to the alien world of Logopolis and witnesses the Fourth Doctor's regeneration. Shortly after on Deva Loka, Tegan's mind became host to a snake-like evil called the Mara. It twice attempted to use Tegan as a conduit to return to corporeal form, an experience that was deeply distressing. Always forthright and often difficult, Tegan bade the Doctor and Turlough an emotional farewell after preventing the Daleks from arriving in 1980s London. According to Sarah Jane Smith, Tegan became a campaigner for Aboriginal rights in her native Australia.