Doctor Who: The Companion Chronicles: The Last Post

People are dying. Just a few, over a period of months... but the strange thing is that each person received a letter predicting the date and time of their death. Throughout her time as the Doctor's assistant, Liz Shaw has been documenting these passings. Her investigation ultimately uncovers a threat that could lead to the end of the world, but this time Liz has someone to help her. Her mother.