The Pale Man was a C19 operative who had been modified with Cyberman technology. He functioned as the liason between the side of C19's official operations (such as liasing with UNIT and running the Glasshouse) and its "darker" side, such as the The Vault. He also was the point of contact for operatives outside of C19.
Prior to joining C19, he lost his arm in an unspecified accident. He was recruited with the promise of a prosthetic replacement, but the actual procedure replaced all his limbs and his internal organs. Due to his partial cyberconversion, he was approximately ten times stronger than a normal human. He was also described as superhumanly fast. He lacked a sense of taste.
He was described as pale, with a scar on his face, and hid the fact that his eyes had been replaced with microfilament discs behind silver-rimmed sunglasses. He invariably wore a light gray suit. (MA: The Scales of Injustice)
The Pale Man later manipulates one of the UNIT soldiers who survived the Axos invasion to capture the Brigadier. He also reveals that his real name is Michael Townsend and tries to change his deteriorating condition by converting to the body of an Auton. but in the end it fails and he dies. (MA: Business Unusual)