The show follows Holmes, a recovering drug addict and former consultant to Scotland Yard, as he assists the New York City Police Department in solving crimes. His indifference to police procedure often leads to conflict with Captain Thomas Gregson (Aidan Quinn), although the two still remain mutually respectful of one another. He is accompanied by Dr. Joan Watson (Lucy Liu), who initially acts as his sober companion. She is a former surgeon and was hired by Sherlock’s father to help him in his rehabilitation