In the novel The Moving Finger, Marcus Kent is a doctor who lives and works in London. He is Jerry Burton's doctor. Jerry believed that Marcus Kent was a good doctor and trusted his advice. Dr Kent advised Jerry to go along with his sister to the countryside, to heal from the injuries he sustained from a flying accident. While staying at Lymstock, Jerry still visited Dr Kent once a month in London.
Marcus Kent is not featured in person in either the BBC 1985 adaptation of the novel or the ITV 2006 adaptation. In the 1985 version, Jerry does go to London for a check up but the name of the doctor is not mentioned.