Three questions those went unanswered in the series:

1)What was Yoon Hae Jun's hidden future that his son mentioned in the last episode? 

2) How did Baek Yoon Young's mother Lee Soon Ae die (in 2021) if she hadn't committed suicide? If she was murdered, then by whom and why was she killed? 

3) In the epilogue of the first 3 episodes we see Ko Min Seok's covered in mud and she has been to the lake side where Soon Ae apparently committed suicide (in 2021). What was she doing there?