After finishing Angel's Last Mission: Love I'm just angry at what this drama could have been.

This drama started so good and had so much potential, but at the end didn't deliver. It had a strong, beautiful first half: interesting plot, charming characters, nice balance of drama, mystery, romance and comedy; and then it went downhill so fast.

Plot stopped making sense, terrible writing turned the characters into over the top caricatures of themselves, interesting characters left unexplored in favor of some cheap drama, zero chemistry between the leads and some over acting.
This is what the show became on the second half.

Neither of the leads were bad per se and most of the flaws I saw in their performance can be blamed on the writing. I think they did their best with what they were given, which to be honest, wasn't much.
Kim Myungsoo is a great comedy actor and his charming performance at the beginning was what made me keep watching; his dramatic scenes could be better but not bad at all. Much better than I expected.
Shin Hye Sun was okay. I think she portrayed the character really well at the beginning, then she started to over act. But as I said, I blame the writing for that.
What I can't ignore is the zero chemistry between them, one of the reasons why I wasn't that invested in their love story.

Quite good supporting actors, with characters far more interesting than the leads at times and that I would have liked to know better because they had so much potential.
And that's what makes me mad about this drama: the fact that it could have been so good, it had everything to be so good, and they chose not to.

At the end, I think not even the writers knew what they were doing.
And it's such a shame because it was so promising at the start.