I would like to start by saying that I definitely enjoyed watching this drama, especially because I am kind of a medical drama fan, but also because it had a bunch of interesting characters, strong acting performances, intriguing plot-lines, great on-screen chemistry, and a witty dialogue.

The story had it's strong and original points, and it also had its normal and not-so original parts.
But all in all, as a medical drama script, this one balanced all the aspects nicely, in a way that saved it from going through the muddy waters that is hospital business wars and all that unrelated areas that many good medical K-Dramas delve too deep into, and end up boring us most of the time (I am looking at you Good Doctor)

As I mentioned the general feel of the dialogue was witty and sharp, a bit quick during the medical scenes, but just within the norm. But the best part was the bickering and fight scenes between the main characters.

The medical part was certainly above average, and although it mainly concerned one branch of medicine ie. surgery, it still showed a wide array of cases and although I am no medical student and my knowledge in the field is null, I could sense that the depiction of the medical proceedings were mostly accurate and delivered in a very professional manner.

The only grope I had with the story, was how the main female lead's PTSD was depicted. At the beginning they sure played it in a way that made it seem quite serious, but then it just kind of magically gets cured with no much as a mention or a proper closure. You are left to satisfy yourself with the explanation that her love overcame her trauma, I guess?

The main OTP as I mentioned had great chemistry and the romance was very well done, it was not the main story line but that's exactly how I prefer it.

As for the characters, I won't be discussing all in detail, I will rather focus on the character that was the first to give me a WOW factor.
One of the first thoughts I had watching the first episode, was "WOW! I love this guy's boldness!!". I won't be going into details lest I reveal any spoilers (it is the first episode but still) but watching the main male lead interact with the female lead right from the beginning, was quite unique and bold, to me it felt like a fresh breeze among all the common self-denials and bashfulness in accepting and acting upon one's emotions that plagues most of K-Drama leads. You don't just give credit to the guy's guts, but you just fall in love with him right then.

The characters other than the main trio (Teacher Kim and the OTP) sometimes felt 2 dimensional, but I couldn't say that that was necessarily a bad thing, because some other dramas try to create separate plot-lines for the side characters, but end up either slowing up the overall pace of the drama, or boring the viewers out with mediocre characters/stories.....or come to think of it in some rare cases, a side-character's plot-line end up being more interesting than the main OTP's and you are secretly kind of watching just to see how it will work ouy, which let's be honest is not a good sign at all! (I am looking at you One more happy ending)

My least favorite character and the thing that felt like one of the weakest points of this drama, was the villain.
At first, when you learn the background story of his animosity with teacher Kim and how their rivalry started, you are convinced of where he's coming from and that there is a long history of clashing between them. But then the more the story develops and the more the villain sharpens his claws and acts out all his villain-y antiques, you start to question the whole character and its motives. Like is it a conflict of interests, is it sheer hatred, is it jealousy, is it pure evil?? You just don't know and kind of don't care any longer.

Another frustration I had with this drama (the direction in particular) was that at many times the details of a certain medical case at hand could be very interesting, and I could be at the edge of my seat waiting to see how the emergency will work out, but then what hinders the whole thing from feeling believable and genuine, is none other than the human/doctors interactions during the procedure, which was at many times packed with overly dramatic acting.
to elaborate more, there is a part where the doctors are arranging for a major operation, and they are struggling to reduce the time required for the said operation as much as possible, like trading even minutes in order to shorten the time the patient is put under anesthesia. But during the actual OP, they find time to waste on looong expressions ranging from staring, glaring, smiling ,clapping and many others.
When you're a viewer of a drama, and you're like distracted from enjoying the thrill in a scene by the characters' facial expressions, then I think it is a sign that the DP/actor should have kept it a notch down.

To sum up, this drama like any other drama is far from flawless but was still a very fun and interesting watch, that I would totally recommend especially to medical drama fans like myself.