Wonderful world started wonderfully but heartbreakingly. It exhibited a saddening aura right from the very first episode.

Wonderful world is what I'd refer to as a "saddening drama"! This is one of the most saddening kdramas I've watched. I mean, the first two episodes completely changed my mood from cheerful to sad.
Eun Soo hyun and Gwon Seon Yul suffered greatly. Soo hyun lost her son, and during those time she almost lost the will to live. Seon Yul lost his father, making his family fall into ruins. The first two leads character are one of the most melancholy characters I've seen.

But it's a good thing justice was served in the end, and the villain was punished. Furthermore, the best of of it all was that soo hyun and seol hyun rose again, and finally got their lives back. And though the ending was a kind of rushed, and it wasn't exactly what I expected, I'd like to commend the actors of wonderful world, they were awesome in their respective roles.
All the actors portrayed their roles wonderfully, especially the first leads.