i think that throughout the whole series the best parts were the episodes 20 onwards although i didn't really like the ending firstly because it was a bit too cliche and "weird" and secondly i felt that the passion and love minzhenghao and changjin had for each other when they were lovers was lost the moment they got married... i guess once u are married there is not much passion needed...
i especially loved the building up of the emotions between changjin and minzhenghao, they didn't just plunged straight into love at first sight but made it more realistic by showing how they admired one another and eventually realising their love for each other... however, i can't really pinpoint when they started liking each other.. but i think that mjh expressed his love first when he realised cj was the one who saved him when she was sent to jeju.. i think that was his turning point... however for cj, she liked him from when she was a palace maid but didn't really show it and kinda buried her emotions until in jeju where mjh expressed his love for her by holding her hands etc. so i guess they began their relationship...
besides, when she was a palace maid she could not like mjh as it would be like having an affair cos a palace maid was considered to be the king's women... but as soon she was a medical lady, she was able to marry mjh.. however as usual due to circumstances they could not do so....
if you watched the series again, u will find that mjh was quite cool and aloof especially when they first met in the library... he seemed quite mean at that point.. then he did it again to tease cj when she was at the city's infirmary... he just wanted cj to express that she wanted him there for her... i think that was weird... well, at least they were two great lovers.. overcoming all obstacles...