Haunted by her tortured childhood and the violent loss of the great love of her life, troubled dental assistant Eni finds escape in Los Cos, a mysterious underground club where cosplay and burlesque intertwine and heroes and villains blur the line between fantasy and reality. But when a cosplayer dressed as "Merman" shows up dead on a New Jersey beach and a mysterious stalker gets up in her DMs, Eni must confront the traumas that have shaped her life and transform herself into an altogether more formidable force.