Broadcasted on December 8, KBS 2TV's 'Entertainment Weekly' featured the 'school attack' segment where Red Velvet made a surprise visit to the Korea Military Academy.

Upon seeing the popular idol group the faces of the military students lit up as they gave the girls a warm welcome into the lecture hall.

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The military students dressed in uniform had no clue what was happening, as they seemed bewildered and surprised by the sudden appearance.

Red Velvet also presented a live performance of "Peek-A-Boo" in front of the class, and took the time to interact with the military students.