Alright. This series is lovable in parts, but also highly irritating in parts, with some repetitive, uncreative and extremely immature plots. This, combined with the fact that Tang Yi (the main character) is almost always frowning and angry, sometimes even while kissing his partner, and that the main job of Shao Fei (the other main character) is to take cuts and bullets for others, makes me want to give the series a 5/10 rating, but nevertheless I will give it a 6- mainly because of these good things:
1. The intense and believable interactions between the various mob guys
2. The initial light-hearted and wonderful acting of the Captain
3. The natural, believable and heartwarming interactions between the second lead couple- Jack and Zhao Li, which I found much more enjoyable and spontaneous than those of the first lead couple- Tang Yi and Shao Fei.
4. The natural and wonderful acting of Chen Wen Hao and Old Tang

Next, I will list the irritating things, so that you are well prepared in advance, and may feel a bit less frustrated, in case you decide to watch this lengthy series. Here we go:
1. During the starting episodes, Shao Fei keeps bugging Tang Yi to reveal the 'truth' based on a hunch. This approach of a police officer is unrealistic and immature, and soon becomes borderline-irritating.
2. Most of Shao Fei's initial interactions with Tang Yi are overly stupid and childish, and make him look like a mindless clown.
3. Shao Fei moving in with Tang Yi, to protect him and to keep an eye on him, was quite unrealistic in itself, but it becomes completely senseless and intolerable when he accepts to babysit Hong Ye, and takes her shopping.
4. Shao Fei's main task as a police officer is not to solve cases, it is not to catch criminals, and it is not to help or protect others with his acquired skills. Then what is it? It is to use his body as a shield for others. And it does not matter who this 'other' person is.
5. Have you realised that every person in this world has two faces? And that every person is confused and conflicted and unreliable? Well, you better believe it, because that is what the storyline tries to portray at the end. Too many persons are shown to be selfish and conflicted, and are just using the others for personal gains. This was completely unbelievable, stupid and immature. I have absolutely no idea why these kinds of plots were suddenly stuffed into the otherwise okay-ish storyline, making it completely ridiculous, so much so that I lost interest completely during the last few episodes.