"Master's Sun" So Ji Sub discovers Seo In Guk's true motives.

August 29, an episode of the SBS drama "Master's Sun" featured Joo Joong Won (So Ji Sub) discovering the fact that Kang Woo (Seo In Guk) is a spy that his own father had sent to keep an eye on him.

When Tae Gong Shil (Gong Hyo Jin) says something that Cha Hee Joo (Han Bo Reum) used to always say, Joo Joong Won becomes surprised and keeps asking about it. Tae Gong Shil tells him that it is something she heard from Kang Woo. Quickly after, Joo Joong Won begins to secretly investigate Kang Woo.

When Joo Joong Won becomes certain that Kang Woo is a spy sent by his father, he begins to question him about whether he was the person working with Cha Hee Joo. Joo Joong Won says, "Tell him to come and explain why he is so curious about it 15 years after the fact" still believing that Cha Hee Joo's death was caused by his father not wanting to pay the ransom.

Joo Joong Won adds, "Father told me to believe whatever I want to believe. I'm desperately trying to find the missing necklace so tell him I hope he doesn't find it."