S1 E1: Idol Star Athletics Championships is here once again with a Chuseok Special. Female idol members compete with each other in rhythmic gymnastics. Among the contestants, Cheng Xiao of WJSN is feared by the rest. For men's archery, BTOB and Monsta X have a match. To the fans and the commentators' surprise, BTOB dresses up as Legolas and Cupid.