Koo Seo-Jin (Hyun-Bin) has two different personalities. One of his personalities is cold like Hyde and the other is sweet like Jekyll.Koo Seo-Jin (Hyun-Bin) has two different personalities. One of his personalities is cold like Hyde and the other is sweet like Jekyll.Koo Seo-Jin (Hyun-Bin) has two different personalities. One of his personalities is cold like Hyde and the other is sweet like Jekyll.