Despite the intensity and gravity of SBS' action thriller 'Three Days', the cast found themselves all smiles in behind-the-scenes pictures, creating a fun and enjoyable atmosphere amidst some tough days of filming.  

Although dressed as a hospital patient with a head wound, So Yi Hyun smiles brightly once she's out of character.  Even Lee Jae Yong, who plays the serious special prosecutor, shows off some unexpected aegyo in two separate photos.

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The production company Golden Thumb Pictures said, "'Three Days' may not be a drama in which the romance stands out, but the actors create a sweet atmosphere on set with their sentimental expressions and amicable vibes.  In addition, when the actors are engaged in their filming, they radiate with more devotion and fighting spirit than anybody else to the point they show a 180-degree difference in personas."

How are you liking the drama so far?