Big Mouth can be summed up into one word: enigmatic. From the start, it was able to build up its very promising main plot with its interesting characters, whom the audience had to guess which side they were really on. It anchored its story’s foundation on the big mystery surrounding the case of Big Mouse and how its main character – who holds the titular moniker – unravels the secret of the infamous criminal.


Admittedly, there were episodes where the story’s intention felt a bit blurry and sort of strayed from its initial promise of a noir legal crime drama. But whenever it stick around to its strongest points, the series remained entertaining enough to finish.
When it premiered, the series showed great potential in how it would develop the character of its central protagonist Park Chang-ho (Lee Jong-suk). He is seemed to be a bit on the quirky side as compared to the archetypical heroes we see in noir series or movies. His softer side made it easier to see his progress while he spends more time inside the jail after he was falsely accused of a crime he didn’t take part in. It also made it easier to root for him since his personal intentions and motivations were clear from the start – he just wanted to live an ordinary and comfortable life with his family.


Chang-ho’s biggest reason to survive the difficult ordeal that befall him is his wife Go Mi-ho’s (Im Yoona). Since this isn’t a romance drama, we only saw bits of their love story and how they are as a married couple. But the actors’ chemistry was undeniable in their flashback scenes and even in their domestic scenes – all of which became a welcome reprieve to all the chasing and tortures happening inside the prison. Romance aside, Mi-ho wasn’t the stereotypical worrying-and-fainting female lead often seen in this genre. Mi-ho found her own way of helping out Chang-ho. It was really a shame that they had to pull a last-minute illness on her. It was an unnecessary character death since the ending could still have worked even with Mi-ho alive. She was the only character I trusted the whole series since the other characters are either the obvious villains or they are friends-to-foe characters.




NR Forum led by Kong Ji-hoon (Yang Kyung-won) was the obvious villain character that makes Chang-ho’s life in prison harder than it already was. But Chang-ho’s entanglement with these troublesome rich men was just the tip of the iceberg. I suspected Gucheon Mayor Choi Do-ha (Kim Joo-hun) from the start and my hunch was proven correct. The ambitious politician was indeed a wolf in sheep’s clothing. He and his wife Hyun Joo-hee (Ok Ja-yeon) are beyond evil. They are ruthless just to protect their personal interests. The head-to-head fight between Choi Do-ha and Park Chang-ho as well as Hyun Joo-hee and Go Mi-ho are some of the exciting scenes in the series. This couple is the exact type of antagonists this kind of series needed.


Aside from Chang-ho’s investigation of how and why he was framed, he was also cornered to find out who the real Big Mouse is. His life in prison mostly revolves around him faking he is the influential criminal and figuring out how it is connected to the murder case that landed him in jail. Big Mouse is obviously playing with Chang-ho which made it difficult to trust anyone Chang-ho meet in prison.


One of the first characters I suspected to be Big Mouse is Jerry / Oh Jin-chul (Kwak Dong-yeon). He appeared bright when he first met Chang-ho and I thought there would be a big character reversal in the end. The character was played by Kwak Dong-yeon after all and he is one good character actor who can play any kind of role given to him. But turns out he isn’t Big Mouse but the lack of surprise with his character is compensated by his friendship with Chang-ho. Although his loyalty was tested at some point, Jerry and Chang-ho teaming up to change their outcast status in prison are one of the most exciting parts of this series. They are underdogs trying to survive in a jail run by those with money and influence.
Chang-ho’s hunt for Big Mouse was marred with evil ploys, betrayals, unexpected collaborations, and violent sequences, which would sometimes feel borderline ridiculous. But if one enjoys such scenes, then Big Mouth has prepared a lot of them. They played out the mistaken identity trope well to make Chang-ho’s plight in the prison exciting to watch. I initially thought they would stretch this trope out until the last few episodes but the reveal of Big Mouse’s identity came earlier than expected.
Turns out Big Mouse is No Park (Yang Hyung-wook) who stayed beside Chang-ho from his day one in jail. I didn’t suspect No Park because he was this father-like figure to Chang-ho inside the prison. And being Big Mouse meant he was just playing with Chang-ho’s life all along. But this wasn’t the reason why the reveal of Big Mouse’s identity was kind of disappointing for me. It was a letdown of a reveal because instead of being this huge end-all-be-all character, Big Mouse turned out to be just a plot device for the last arc to continue.


Big Mouse turned out to be a leader of a gang-like organization and Chang-ho has been surrounded by its members all along. The real last battle wasn’t between Chang-ho and Big Mouse. The last Great War he had to face was accepting the role he was forced into. He had to choose between the lesser evil since he couldn’t anymore go back to his previous ordinary life as a lawyer. The directions the series took in the last arc are questionable but the series still had a great run. Big Mouth still has some great exciting episodes and was a thrill to watch from start to finish.