Elizabeth Klein

Biography
Doctor Elizabeth Klein was born in an alternative timeline, one where Nazi Germany won the second World War. She was tasked with examining a strange blue box found in Colditz Castle in 1945. Mastering use of the device which turned out to be a time machine, with the aide of the mysterious Johann Schmidt, Klein traveled back to the day the box was discovered. The Doctor prevented the alternative timeline from coming about, however stranding Klein in the traditional universe.