Aw, how cute. SBS's 'Six Flying Dragons' might be a serious and intense periodical drama, but co-stars Shin Se Kyung and Yoo Ah In prove that they can still have fun during the tough filming!

Behind-the-scenes cuts unveiled on November 2 show how the two stars smiled brightly and seemed to be in cheery moods despite the tough horseback riding scene. They were even playful, flashing V-signs at the other staff members, probably making their joviality contagious.  

However, once they had to start filming, the two actors changed completely, getting into their grave roles and showing an admirable professionalism. A rep stated, "They are always considerate toward each other even within the laborious filming. The laughs never cut off thanks to the valuable hard work of the actors."

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Are you enjoying their chemistry and the drama so far?