It's no surprise that the cast members of 'Reply 1988' have great chemistry on screen as we witness every week with each episode airing. To further show off their great synergy, this week's special airing was of behind the scenes footages that started prior to the actual filming.

For those who have been following up with the series will also be aware that there is a love triangle between Hyeri (Duk Sun), Park Bo Gum (Taek), and Ryu Joon Yeol (Junghwan). The butterfly-in-stomach kind of love and emotions between the three have seemed to have transferred over off-screen as behind the scenes footages showed Hyeri and Ryu Jun Yeol fooling around during their down time.

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In addition to Ryu Joon Yeol, Hyeri was also seen being adorably friendly with Park Bo Gum, who has appeared on Hyeri's Naver 'V' broadcastings on multiple occasions, during the special edition episode of 'Reply 1988.'

Whether Duk Sun ends up with Junghwan or Taek in the seires, their off-screen friendship seems to go far beyond what we see.