Sleeper hit

In the entertainment industry, a sleeper hit is a film, television series, music release, video game or other entertainment product that was initially unsuccessful on release, but eventually became a surprise success. A sleeper hit may have had little to no promotion or lack a successful launch, but gradually develops a fandom and spreads via word of mouth, media coverage, or unexpected internet virality. As Variety puts it, “A ‘sleeper hit’ can be defined as the kind of show that catches us by surprise—programs whose popularity grows over time and can ultimately outshine the preordained hits.”