On December 11, tvN's retro drama 'Reply 1994' released a preview for the 16th episode.  To everyone's excitement, this preview included a clip of both Eunji and Seo In Guk making their long-awaited cameos as they had starred in the original series 'Reply 1997.'

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On December 10, tvN's 'Reply 1994' Twitter left a message, "It is correct that all five from 'Reply 1997,' Si Won (Eunji), Yoon Jae (Seo In Guk), Yoo Jung (Shin So Yul), Sung Jae (Lee Si Eon), and Joon Hee (Hoya), will be making cameo appearances in this week's 16th and 17th episodes.  I hope it would be a welcoming scene for the 'Reply 1997' cast."

Make sure you watch this week's episodes to see an excellent overlap between the 'Reply 1997' and 'Reply 1994' stories!