Horatio Caine formerly worked in New York City as a detective with the NYPD, much like Caruso's NYPD Blue character Det. John Kelly, before moving to Miami. He killed the man who murdered his mother; his own father. In 1995 he was stabbed while investigating a case in which children were locked in closets while their parents were murdered. The perpetrator, Walter Resden, harbored a grudge against Horatio, collecting the blood from the stabbing and preserving it for 10 years in order to frame him for the murder of Horatio's girlfriend, Rachel Turner.