Acquaintances of a celebrity (friends, managers, parents, siblings, etc.) are invited to answer a quiz about the celebrity to see if they know him/her as well as they think they do. For instance, they will have to watch videos of the celebrity and predict his/her next actions.
For Season 2, a slightly different change is that 4 guests related to the celebrity are invited to the show and take on the Non-related Observers (the cast members except Jang Sung-kyu) in a quiz about the celebrity. A total of ₩3,000,000 is up for grabs and the team with more winning money wins the quiz.