For a drama about the chinese civil war, this is actually a quite interesting and a refreshing twist to the normal story line for this kind of drama. The story line is quite complex, there's a quite a bit of mystery and scandals going on throughout the drama which only we the audience and the parties involved know about until it all gets exposed in the end.
One of the two downsides to it is probably the production; the action scenes seem too well synchronised to be realistic and the props used frankly resembled something brought from a toy store. And then of course there was the female lead. Tiffany Tang is well known for taking silly Mary Sue roles and this role did not disappoint. Everyone else seems to take their role extremely seriously and was convincing enough to be special agents, only she was....let's say luck was always on her side so she didn't need to do much in order to survive and succeed. But hey, I got to like her in the end, as the drama could be quite depressing and dark sometimes and you could always guarantee she would cause some sort of trouble to lighten things up again or see her be tortured.
But overall it was an enjoyable drama and I would really recommend it.