Charlie Mortdecai, an amoral art dealer and aristocrat, finds his attempt at a quiet exile in Jersey interrupted by a series of gruesome crimes that force him into the role of an unwilling investigator. Seeking refuge from his mounting unpopularity in London, Mortdecai attempts to settle into a life of hedonistic leisure on the island of Jersey. His plans for a peaceful interlude are thwarted when he becomes entangled in a hunt for a local predator whose methods mirror those of a legendary mythological figure. The narrative is presented through the distinct, cynical, and often unreliable voice of Mortdecai, who navigates the social and physical landscape with a mixture of cowardice and opportunistic wit. He must contend with both the local authorities and the dangerous reality of his surroundings while maintaining his own precarious lifestyle.

Readers frequently highlight the sharp, sardonic wit of the protagonist as the primary draw of the series. Discussion often centers on the balance between the dark, macabre subject matter and the author's lighthearted, almost flippant prose style. Critics often note that the pacing is dictated more by Mortdecai's personal whims and observations than by traditional thriller mechanics. Many fans appreciate the character's unapologetic amorality, which distinguishes the work from standard detective fiction. The series is widely regarded for its unique voice and the specific, cynical perspective it offers on the art world and high society.