Trainee designer Ye Xuan dreams of working in an advertising agency, but she has not been transferred to a permanent contract for six months, and all she gets is a lot of small, featureless orders. Finally, an interesting advertising project appears, and Ye Xuan takes it up with enthusiasm to demonstrate his professional level. However, there is still a certain «side A» — its competitor. To cope with stress at work, the girl is helped by a strange neighbor Li Jinan, with whom Ye Xuan is having an affair. Who would have thought that he is the dark «side of A».