As fans already know, Seo In Guk is starring in the upcoming film about swimming, 'No Breathing', and he didn't hesitate to show off his newly formed swimmer's body!

Seo In Guk must have missed the cast of 'I Live Alone' so much that he returned to the show for a surprise visit. On the July 12th broadcast, he had perfect timing as the cast were discussing the topic of women and revealing clothing when he walked in, which led the guys to ask Seo In Guk to reveal his top half. 

The singer-turned-actor then turned around, while Noh Hong Chul lifted up his shirt to show off the new muscles he built for his role in the film.

The cast then asked if Girls' Generation's Yuri, who is also starring in the film, had any revealing scenes, and Seo In Guk replied, "No," disappointing everyone.

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