Dr. Grace Holloway is a heart surgeon at a San Francisco hospital. The Doctor is brought to her hospital as a result of injuries suffered from an accident to his TARDIS. He regenerates, though more from the reaction to the treatment he is given than to his original condition. He ends up taking Dr. Holloway along with him as he attempts to foil the Master's latest plot.
More information as it becomes available.
Sheer speculation: There will be the faintest hint of romance between her and the Doctor, but it will never amount to anything, at least not onscreen.
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