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According to the drama's rep on the 14th, Lee Joon made a cameo for the 19th episode out of his connection with 'Gabdongi' director Jo Soo Won. He filmed the cameo outdoors on the 11th as seen above, and despite the cold weather, he showcased his professionalism by taking on his role with sincerity, impressing the staff.

The producer stated, "Thank you to Lee Joon, who readily decided to make a cameo out of his connection with director Jo Soo Won. Although it was only a cameo, we were touched by how he passionately and sincerely took on filming. We ask that you look forward to his appearance."

Stay tuned for his cameo in the upcoming back-to-back episodes (18 & 19) today!