Chul-soo is a man with an intellectual disability. One day, Chul-soo finds out that a young girl, Saet-byul, who is in hospital is his daughter. And soon, Saet-byul sneaks out of the hospital and travels by herself to a faraway city for her friend's birthday. As Chul-soo accompanies Saet-byul's journey, friendship develops between the two.

A teenager gets her hands on a note that enacts revenges on anyone whose name is written on it.

P4: are the new recruits in the violent crimes unit at Gangnam Police Station. The journey of four young cops as they fumble, learn, fall in love and find their way to becoming people the citizens can trust.