Mary Seacole

Played by Sara Powell

"If we all of us waited to be sent for, we would none of us find our purpose, would we? I paid for my own passage, and I had this place built from what I could find."

The Thirteenth Doctor was aware of Mary Seacole before they met: but what she remembered was an angel of mercy helping the casualties of a conflict between British and Russian soldiers - not someone lost in the chaos of Earth's first war against Sontarans!

Born in Kingston to a Scottish soldier father and a Jamaican healer mother, Mary travelled to the Crimea to assist in nursing: when her application has been refused she had gone anyway, self-funding her trip and setting up a hotel to tend the battlefield wounded.

It was as she was carrying out this work that she met a stranded Doctor, taking her in and trying to answer all the bewildered Time Lord's questions, unaware that time had been changed by a Sontaran infiltration. Her sense of mercy had resulted in her tending an alien casualty and it was the information she learned from Sontaran Svild that provided the key to the Doctor defeating the Sontaran battalion as they recharged.