Boom made his first official television appearance, after returning from his two-year mandatory military enlistment, on the September 6 broadcast of SBS’ “Strong Heart”. In this highly anticipated episode, Boom revealed several stories from his time in the military, made more interesting by the fact that he was in the PR division along with many other celebrities like Kim Jae Won (“Can You Hear My Heart”), Lee Dong Wook (“Scent of a Woman”), and Andy (Shinhwa).

Boom recalled the first time he entered the PR division after completing the initial 4-week training camp. Kim Jae Won was a sergeant in the division at the time and he pretended to not know who Boom was, even though Boom had interviewed Kim Jae Won before. So Boom started dancing his signature “Who?” dance for 20 minutes but Kim Jae Won would not smile. Boom continued to show off some impersonations until Lee Dong Wook, a corporal at the time, dragged him to the roof and gave him special training on impersonations.

The next day, Boom witnessed a fight begin between Kim Jae Won and his army senior Jae Hee (“Witch Amusement”). Boom, concerned that Kim Jae Won was arguing with a higher-ranking officer, tried to stop them only to see the two clash… in a chicken fight! It was revealed later that it was all just an elaborate “hidden camera” type welcome ceremony for Boom that the PR division had prepared for a month.

Boom exclaimed, “Imagine, a “hidden camera” event with real actors. I was honestly scared.” He happily added, “I couldn’t sleep at night because I was so grateful that everyone would think so much about me.”

Along with Boom, SNSD’s Sunny, Hyo Yeon, and Seo Hyeon also appeared on the Tuesday episode of “Strong Heart.”