Smiler

The Security Monitoring Integrated Liability Enabler or Smilers were a type of android used aboard Starship UK.

History
The Smilers were mounted in booths around the Starship UK. When adults broke the law or were deemed unnecessary, the Smilers would feed them to the star whale; children were sentenced to work in the Tower of London. The Smilers rotated their heads to show three faces: happy, displeased (for warnings) and angry (when attacking). While they had three faces, they appeared to rotate their heads halfway around, which should mean they only had two. This might mean that faces were removed when they rotated.

While Smilers appeared to be merely heads, in extreme circumstances their entire bodies would leave their booths and attack. The terrified population never dared approach the booths, which had the effect of the area surrounding the booth being almost spotlessly clean, as the Doctor noticed. The Smilers quickly recovered from damage such as being shot.

Humans hybridised with Smilers were known as Winders. They formed a secret police force that maintained the clockwork machinery on Starship UK. (TV: The Beast Below)