Detective Michael Scott Kellerman is a fictional character on the television drama series Homicide: Life on the Street portrayed by Reed Diamond.

Kellerman had recently been divorced from a crime lab technician named Anne Kennedy prior to his joining the homicide unit.

With the squad short three men (Stanley Bolander and Beau Felton on suspension, Steve Crosetti dead by suicide), Lieutenant Al Giardello offered Kellerman a transfer to Homicide, having been impressed with his work on the cases.

Early in the fifth season, a federal grand jury was gathered to investigate corrupt cops in the arson unit, including Kellerman.

Falling into intense depression and reeling from another case of Luther Mahoney getting away with murder, Kellerman became increasingly angry and almost committed suicide.

They consoled each other with a one-night stand, then developed a rough-edged, informal relationship that continued until Cox was fired and left Baltimore in the sixth season.

Kellerman and Lewis were put in charge of a string of murders linked with drug kingpin and crime lord Luther Mahoney (Erik Todd Dellums).

Eventually, a drug mule who had been transporting heroin from overseas was discovered dead in his motel room after one of the heroin-laden condoms in his stomach burst.

Gibbons was found stabbed to death shortly afterward, with evidence pointing to Georgia Rae's son, Nathaniel Lee "Junior Bunk" Mahoney (Mekhi Phifer).

Although he was ultimately shot dead by Bayliss, Lewis, Kellerman, and Giardello, Detectives Gharty and Ballard were injured and three uniformed officers were killed.

Pembleton and fellow detective Paul Falsone interrogated Lewis and then Kellerman, who eventually admitted that Mahoney had lowered the gun before being killed.

While testifying for the benefit of the teenage mother in Kellerman, PI, 2 Mike becomes the first of the Baltimore detectives to explain the "Board" and what it means for a case to go from red to black.