Surgeon (World Enough and Time)

The surgeon was a Mondasian who lived on floor 1056 of a Mondasian colony ship caught in the gravitational pull of a black hole.

At some point he advocated the creation of cybernetic humanoids in order to ensure the people trapped at the bottom of the ship could survive the journey to the top, as they lived in two separate time streams, their own moving much slower than on floor 0. He met Bill Potts, telling her of how he would inhibit her emotions before proceeding to convert her into a Cyberman.