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Lee Jong Suk was spotted enjoying some fresh air alongside Yoo Jae Suk, while Park Bo Young looked tiny next to the 'giraffe' Lee Kwang Soo on set at Yangju, Gyeonggido. Fans also noticed Kim Jong Kook's name tag reads, "Kim Jong Sook," making them wonder what hilarity will come about during the upcoming episode.

A movie rep commented, "Lee Jong Suk and Park Bo Young will feature as guests on 'Running Man'...The broadcast date has not been decided yet. It will air sometime during the movie promotions period."

'Young Blood' ('Blood Boiling Youth') will open in theaters this January!