Jumping the shark is the moment when something that was once popular, but that no longer warrants the attention it previously received, makes an attempt at publicity, which only serves to highlight its irrelevance. This is especially applicable to television series or other entertainment outlets.[1]
The idiom "jumping the shark" is pejorative, most commonly used in reference to unsuccessful gimmicks for promoting something. It is similar to "past its peak", but more specifically suggests an unwillingness to acknowledge the fact. Originally, the phrase was used to describe an episode of a television comedy with a gimmick or unlikely occurrence desperately attempting to keep viewers' interest. Moments labeled as "jumping the shark" are considered indications that writers have exhausted their focus; that the show has strayed irretrievably from an older and better formula; or that the series as a whole is declining in quality.
The phrase derives from a scene in a Season 5 episode of the 1970s sitcom Happy Days in which the character Fonzie jumps over a shark while on water-skis.[2][3][4] This gimmick strayed absurdly outside the original storyline of the sitcom.
The usage of "jump the shark" has subsequently broadened beyond television, indicating the moment when a brand, design, franchise, or creative effort's evolution declines, or when it changes notably in style into something unwelcome.