Lydia (Too Many Masters)
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Lydia was on the the slaves the Ogrons have.[statement unclear] She told Missy that she was a time traveller and was captured because of it. She flirted with the Monk in order to find the location of his TARDIS. She went to the library to find more about the sacrifice ceremony, not realising that there was a librarian. She was killed by Missy after entering the Monk's TARDIS. (AUDIO: Too Many Masters)