
The Mermaid Prince

Tells the romance story of a girl named Hye Ri. She goes to Gangwon Province on a graduation trip with her friends. There she meets a mysterious man Woo Hyuk who runs a guest house. She gets attracted and closer to him and decides to name him “the mermaid prince”.
It's the same actor, with the same name in both "seasons" but they're actually completely unrelated stories.
Season 1 is quite bad. The production quality is terrible (it looks very cheap and amateurish) and the story is not good either. 5/10
Season 2 is a completely different beast. It looks and feels much more professional and polished, all of the stories and complicated relationships are more interesting and the acting is all around better, too. 7.5/10
I'd say skip season 1 and just watch the second one.