The series follows Adrian Monk, a brilliant former San Francisco detective, who now consults the police as a private consultant whilst battling with an obsessive-compulsive disorder.

After the unsolved murder of his wife, Adrian Monk develops obsessive-compulsive disorder, which includes his terror of germs and contamination.

His condition costs him his job as a prominent homicide detective in the San Francisco Police Department, but he continues to solve crimes with the help of his assistant and his former boss.