"Knowing Bros" is a popular South Korean variety show that features a fixed cast of male celebrities who act as high school students. The show is known for its humorous and candid discussions, where guests, often fellow celebrities, join the cast to share stories and participate in games. The format includes various segments, such as quizzes and skits, which encourage interaction between the cast and guests. The show has gained a large following due to its entertaining content and the chemistry among the cast members, including Kim Hee-sun, Lee Soo-geun, and Seo Jang-hoon.