The 'dad's' mention of being all in the same boat raises possibilities of them being in league over nefarious deeds, either in the past or still on-going.
Hee-sung says that Moo-jin is holding in the question he wants to ask, and Moo-jin tries to leave, but Hee-sung tells him to ask the question.
As she digs into his mysterious past, she discovers many secrets.
The cast was led by Lee Joon-gi and Moon Chae-won, who also previously worked together in the 2017 TvN drama Criminal Minds.
I would have used paper cups for the poisoned tea.
The medicine makes Ae-young slow and out of it, so that even when she found on his collar one time, Sung-jin was easily able to convince her that it was paint.