He said, "When I first heard the leading actress will be Kim So Yeon--honestly, I was a bit scared of her since watching 'Iris'... I thought things like 'I'm going to get in trouble' and 'I'm going to get hit,' but when I first met Kim So Yeon on set, I was surprised by how kind and cautious she was... I did not expect to see the noona as a feminine girl more than the action star I knew her as."

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Sung Joon also talked about their team work on set, saying, "In relation to our working together, noona treats me really well so I thought, 'I better start depending on her quick,'" and am working hard."