Before I get into anything else, just let me highlight the strong points of this drama. It has a wonderful supporting cast that does not let up, the OST is powerful, and it is truly a cinematic masterpiece. Beware, long post.

The biggest flaw of this drama was the initial conflict; every good story needs a conflict in order for it to progress. In the case of Start-Up, its central conflict is lying. Almost all the main characters lie in order to drive the story, and at some point you may find yourself going crazy over it. The order of most honest main characters go as so: Dal-mi > In-jae > Ji-Pyeong = Do-san > Won-deok. Yes, the extremely wholesome grandmother that may make you cry and go soft in her scenes with Ji-Pyeong is at the bottom.

Although her intentions were good, she based her granddaughter's entire childhood off a lie. Not only did this bolster Dal-mi into bluffing to In-jae, but Ji-pyeong's letters later culminate into a high tension love triangle all at the expense of Dal-mi's feelings. When the truth is revealed to Dal-mi, it is supposed to highlight positive traits to her character. We do not see resentment towards her grandmother, only disdain targeted at Ji-pyeong and Do-san. Had I been Dal-mi, I would have felt incredibly mortified; as though I had been pitied by my grandmother.

Let's get to Do-san and Ji-pyeong.

I just have to say Nam Joo-hyuk knocked it out of the park. Those saying Do-san was dull and not a worthy ML are missing the point and have been blinded by the shining light that is Kim Seon-ho's acting ability. NJh did his job. He was supposed to portray to us an awkward, gawky, and passive programmer who had zero experience with women, someone who had never truly been driven by anything deeper than a fondness for coding, and finally for once in his life, he felt like he had a purpose. I for one related to Do-san at some points. He felt like he was in competition with Ji-pyeong the whole time but it was untrue. You can always envy another person who seems like they have it all and it will blind you into insecurity. Ji-pyeong said it best to him towards the end of the series, "Work on your self-esteem, look at Dal-mi once again, and then ask yourself who you think she truly likes." Do-san was always in competition with himself, it is an underdog story.

Kim Seon-ho's acting makes you fall in love with him. Time and time again, he has a knack for heart-melting expressions, it's that icy exterior but surprisingly wholesome interior that makes Ji-pyeong so bewitching — and KSh delivers it perfectly. After all, who doesn't love a rags to riches story with humble beginnings (backed by an affectionate relationship with a stubborn grandmother)? Again, just like Do-san is supposed to seem inferior, Ji-peyong is supposed to seem perfect. But he also lied in the end, not just to Dal-mi for Won-deok, but he lied to himself. Because he could not come to terms with his feelings fast enough, for that, he was dealt the ending he deserved. I'm sure there are others who will come to his defense, but as much as I rooted for him myself, Dal-mi also was not attracted to him. The writers teased us in the three year period where they became close, they almost made us think she might end up with him.

I was a little disappointed with In-jae's story involvement. While the rekindling of their relationship as sisters was subtle, it kind of went from cold to hot very quickly. I also didn't like that she ended up stealing her sister's story so she could make it into SandBox. Again, so much lying. Samsan gets acquired by 2STO and what? Dal-mi suddenly has her respect? We were also robbed of their budding partnership in that three year period. To add a little bit more onto that, I felt that her character had been stunted and she could have had more redeeming qualities other than "coming clean about the SandBox girl." People say they assume she ends up with Ji-pyeong, but I actually think this is wrong. I think it is implied in the last episode she and Yong-san have a little something there. That way, it kind of completes the whole "every Samsan guy gets a happy ending."

An honorable mention: Sa-ha and Chul-san. Truly the diamonds in the rough of this drama. Their side romance was honestly so enjoyable and really refreshing. By being honest and straightforward, the inexperienced nerd attains the love of a seemingly unattainable beauty who is, not only emotionally intelligent, but incredibly funny and witty. I wish we had gotten more of them in the last episode.

If you don't understand Korean and have not looked up a translation to the OST, Day & Night, by Jung Seung Hwan, I urge you to. Every time they played the song it almost brought me to tears; a very lovely meaning that very well captures how the male leads both feel.