A boisterous detective goes undercover in a high school in order to befriend the teenage daughter of a notorious gangster.

Former Scissor Gang leader Eun-jin, who now suffers from amnesia, nevertheless defends Jae-cheol, a restaurateur who employs her, from a gangster who wants his business.

A staircase leading to a schoolgirls’ dormitory usually has 28 steps, but sometimes a 29th step appears. Any wish you make while standing on this step comes true, even if…