The Chief Caretaker was the leader of Caretakers in Paradise Towers.
Biography
Unknown to his staff, the Chief had found a creature in the basement and taken it as his pet. He had the cleaners take it the bodies of the dead, believing that it ate them. The Chief even went so far as to have Caretaker 345/12, subsection 3 killed to feed the creature He though of himself as the creatures "daddy".
When the Seventh Doctor was brought to him, the Chief took him to be the "Great Architect", namely Kroagnon, who built designed Paradise Towers. He then ordered his execution and was called away after a report on the death of 345/12, subsection 3 came in. When he returned, he found that the Doctor had escaped and blamed the Deputy Chief Caretaker who was tasked with him re-capture.
The Doctor was once again brought before the Chief who began interrogating him. He soon found out that the Doctor was not the "Great Architect" as he had though, but still ordered his execution. Once again he was killed away after a report on the death of Tilda and Tabby came in. He went to the scene of the death and bribed Maddy by offering her the flat in return for her silence on the matter.
While making his way back to control, he met with cleaner 479 who forced him down to the basement. There he ws brought before the creature who revealed itself to be Kroagnon and that he needed a body to escape from his imprisonment. The Chief was then forced into a contained and corpoelectroscopy was performed to transplant Kroagnon's mind into the Chief, effectively killing him. (DW: Paradise Towers)