Drama might not appeal to all but definitely did to me. The synopsis is pretty accurate in the description. Our Heroine Todo became a detective because she wants to discovery the boundary that turns some people into criminals. This whole exploration of the dark side of humanity is the main appeal for me, and the continuing conversations about this subject throughout the drama is what made me enjoy the drama. Granted it didn't go as deep as I'd wanted to, and one of the best villains here felt like a copy of the villain in Siren, it was interesting nonetheless. As far as storytelling goes though, don't expect all to make sense, but just works out in the universe of the drama. Todo is a pretty intriguing characters. I liked following her trail of thoughts as she makes the (obvious) connection between cases and follow her investigations on her own. What I enjoyed most is her personality. She's definitely one enjoyable to have around since she's agreeable for the most part, but there definitely is this invisible wall around her. Once through that wall, you may find something completely different than the impression she gives at first. Another intriguing character would be Nakajima. I enjoyed most the conversations people have with him. I thought it was only his conversations with Todo that interest me, but even around others like Shoji, he never ceases to be interesting. Honestly though other than Todo, Nakajima, and sometimes the Queen of death, none of the other characters were remotely interesting, and were there to fill space and add on the usual tropes. If more depth and screentime was given to all the characters, and whole police were not made so dumb, it would've been one of the greatest dramas. I mean how could you call yourself a detective when you're incapable of making such simple connection. Also the way Shoji does his investigation is just such a sloppy way to portray! Everyone else was useless. Well the forensic department also had its moment. As for the cast, casting Hayashi Kento was the BEST thing they did. He really carried the drama for me. I didn't like Haru much but I warmed up to her here. I always enjoy Watabe Atsuro on my screen but felt underused. Still he had quirky personality traits. Harada Mieko was a welcome addition to the team and her scenes her fun. First time watching Yokoyama Yu and OH MAN HE WAS ANNOYING! A total grumpy ojisan! And it doesn't help that he looks SO MUCH younger than his age. The rest of the cast aren't worth mentioning. Except the guest role actors, like Mamiya Shotaro, left an impression as well. Quality wise, I'd give it 6-6.5 rating. However when factoring in my enjoyment I had of it I had to boost it up.