The drama had an amazing idea for a great character, but somehow it has slowly been losing the charm the closer to the end we've got.

CHARACTERS
While the writer had a clear idea for both male lead characters, Dong Sik and In Woo, and both of their stories were quite well developed and concluded, Shim Bo Kyung was left to do what usually side characters do - react the right way to progress the plot.

Dong Sik, the definition of a loser, because of a quite humorous and coincidental string of accidents takes the persona of a serial killer. Having an amnesia and being faced with the reality of either being a pushover or a serial killer, he thinks of the former being more painful and scary and he accepts the possibility of being a psychopath, rationalizing all of his humane and empathetic behaviors for them to fit his new identity.

Seo In Woo, a serial killer who thinks he found his soulmate and killing partner in Dong Sik. His growing obsession over Dong Sik leads him to also credit the main lead with more wits, smarts and planning skills than he is capable of. Never being cared for by people in his environment, he hopes for a place of understanding in Dong Sik.

Shim Bo Kyung, who wished to be a detective until her father's accident. Since that time she kept having hallucinations of her father at the prime time of his career. The hallucinations were nothing more than her repressed hopes and wishes to follow his footsteps in the crime department. Sadly, her character in most cases was just used to forward the plot, the idea of hallucinations was not addressed enough. Not to mention her character was extremely inconsistent in terms of her skills. At times she had amazing intuition and deductive skills, but at the same time she failed to notice and connect many, quite obvious clues.
The combination of these three characters made quite an interesting and entertaining story and the ever changing interactions between them made me question who at the moment has the upper hand.

ENDING (no spoilers)
The fact that the ending was quite predictable from the get go was not a problem, since this drama focuses more on the journey not the destination.

PROS
Good acting of all the main and supporting actors, a variety of different characters that make it easier to find someone we can relate to, extremely good chemistry between Dong Sik and In Woo and the shifts in the dynamics between them.

CONS
Too much comedy took away from the serious aspect of the drama and made the villain less scary and impactful (he is a serial killer after all), unrealistic portrayal of police work to the point of it being ridiculous at times, less entertaining second half of the drama, not a strong first episode.