Yoo Ah In and Shin Se Kyung are all smiles during filming of 'Six Flying Dragons'

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?