The forerunner of mystery, cases, accidents related shows unveils its new appearance to mark its 20th anniversary. The secret agents of ＂Surprise＂ among celebrities gather with utmost secrecy to reveal the behind stories of the show that couldn’t be aired, including mystery, history, conspiracy theories, and many more. The four secret agents are invited to this Secret Room, Jung Hyung Don, who has become the successful fan of ＂Surprise,＂ Jang Sung Kyu, who will solve the puzzle of the room with flashy talking skills, Hwang Je Seong, who will compete against the ＂Surprise＂ maniac, Jung Hyung Dong with his mysterious eyes, and Cho A, the dark horse who analyzes the cases with sharp remarks. We invite you to ＂Surprise: The Secret Room＂ as special agents. Find out what terrifying story lies behind the door of this secret room!