Mr Smart (The Man Beyond Time)

Mr Smart is a Cyberman head the Doctor obtained at the Maldovarium Market to replace Handles.

History
Mr Smart was a Cyberman in the 51st Century, who was captured by Human forces, and deactivated so they could access the information in the Cyberiad hive mind. His human parts were removed and once his usefulness was gone, the mechanical parts were sold to the Maldovarium Market.

The Doctor
After a while, the Doctor visited the market while he was preparing for his retirement. Feeling he'd need a friend, the Doctor bought the head, and later modified him to add emotions to his programming.

Personality
Like all Cyber units, Mr Smart was emotionless. The Doctor added to his coding to give him emotions, expecting him to be nice like Handles. To an extent it worked, but it isn't uncommon for him to be mean to the Doctor and Clarke.