This partnership initially worked reasonably well, but had some strains as Kellerman slid toward alcoholism and humiliation when he was falsely accused of having taken bribes while in his previous position.

Lewis and Kellerman had earlier found themselves arguing with each other over a Nation of Islam group acting as a private security force in a Baltimore City housing project.

He persuaded fellow detective Paul Falsone to feed him information about the organization, which he used to start an internal war that eventually led to a bloodbath for both the police and the criminals.

Lewis refused to partner with any of the female detectives in the unit until the final episode, in which he and Sheppard achieved a reconciliation of sorts and began to work a crime scene together.

According to the Season 4 episode "I've Got a Secret," Lewis had a mentally ill brother named Anthony, who was institutionalized roughly 20 years earlier as he was a danger to himself and others.

Lewis had a harshly realistic view of the job, and was openly critical of Tim Bayliss for putting so much of his emotional energy into the unforgiving field of police work.

"[6] Clark Johnson regularly improvised during filming and made up his own jokes and dialogue; writer and producer James Yoshimura called him "the king of the ad lib.