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The two were promoting their new film 'Grandmother Gye-choon,' on which they play grandmother and granddaughter. The movie is based on the laborious, tough lives of Jeju Island's haenyeo (female divers), who scour the ocean floor day and night for fresh abalones. 

Yoon Yeo Jung and Kim Go Eun, both of whom actually had to don SCUBA gear and dive into the sea for filming, admitted that they were only able to endure the difficulties with wine. Yoon Yeo Jung blurted, "We were in our cups during filming," to which Kim Go Eun could only bow her head and laugh in embarrassment.