The program invites a celebrity's close acquaintances, including friends, managers, parents, siblings, etc, to answer video quiz questions about the celebrity based on his/her personality and habits as observed by the acquaintances. Footage of the celebrity guest's daily life will be played in front of the acquaintances, and they must try to guess certain actions which will follow in a quiz format. 

'I'm Not The Person You Used To Know' will be MC-ed by Lee Soo Geun, Jang Do Yeon, NU'EST's JR, and DinDin, and according to reports, the MC cast recently wrapped up their first recording together. The Mnet show is expected to air some time in December, so stay tuned!