Columbo is a shrewd and intelligent blue-collar homicide detective whose trademarks include his rumpled beige raincoat, unassuming demeanor, cigar, old Peugeot 403 car, love of chili, and unseen wife (whom he mentions frequently). He often leaves a room only to return with the catchphrase "Just one more thing" to ask a critical question.

The character and show, created by Richard Levinson and William Link, popularized the inverted detective story format (sometimes referred to as a "howcatchem"). This genre begins by showing the commission of the crime and its perpetrator; the plot therefore usually has no "whodunit" element of determining which of several suspects committed the crime. It instead revolves around how a perpetrator known to the audience will finally be caught and exposed. The clues Columbo finds to help him solve the case are sometimes revealed to the audience beforehand, but often not until the episode's end.