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On the April 6 episode of 'I Live Alone', the cast members of the 'Rainbow Team' went to the Catalina Islands to meet Daniel Henney.

As they met, the members immediately greeted the actor by approaching him 'the American way', with most of them chest-bumping or hugging him one-on-one. Meanwhile, Han Hye Jin also went to greet Daniel Henney enthusiastically, as naturally as the other members.

However, in that moment, Jun Hyun Moo's facial expression drastically changed. Showing intense signs of petty jealousy, Jun Hyun Moo was caught on camera, glaring at Han Hye Jin hugging Daniel Henney! After that, he murmured to himself, "Why is she hugging him, all of a sudden?" (Remember, the filming for this episode took place before the couple went public with their relationship.) 

As the 'Rainbow Team' all watched the scene together, Jun Hyun Moo confessed that he could not hide his expression back then. Han Hye Jin explained that it wasn't a hug but a French way of greeting each other by the cheeks (the 'baiser'). But, Jun Hyun Moo still did not let go, apparently still jealous from the incident!

"Look at my facial expression. Please make that into an emoji," said Jun, jokingly.