the storylines of both drama are quite different but similar at the same time. Both are about the rich & privileged people who used their privilege and power to step on other people. The characters in both dramas hide murder and their crimes together to save their elite status, also Bong Tae Kyu and Yoon Jung hoon are in both dramas as friends, accomplices or partners in crime. Even characters of Bong Tae Gyu(Lee Kyu Jin) in both dramas are similar(childish & stupid). Anyway both dramas has the same feeling and ambiance.

Fun Fact: As first Shin Sung Rok(ML in Return)was to play the main character of Joo Dan Tae which is later replaced by Um Ki Joon due to schedule conflicts.

Both dramas center the three long-term female friends and the plots are simple yet show a slice of life in a comedic relatable way. Both are the kind of dramas which we can cry and laugh and feel relatable at the same time. And Im jin joo and Yoon Ji Ho give off the same vibe, both are the scriptwriter and brave yet weird in some ways.