Mysterious Lotus Casebook is a drama that I didn't expect to like as much as I did, and it's not because I expected the story not to be good, but because I haven't watched something as captivating as this in a long time. I finished 40 episodes in 3-4 days (and it would've been sooner had I not had other responsibilities). The story is not perfect. It follows Li Lian Hua and Fang Duo Bing, who in search of answers for something that happened 10 years ago and caused two biggest sects of martial arts world to collapse, become detectives and solve a myriad of cases. Now, the cases could've been better, I'm not gonna lie. Both the investigation part and the crime part. Many of them were kinda far-fetched and hard to believe and the investigation consisted mostly of characters just looking around the crime scene and miraculously figuring everything out. There was no real suspense. However, what I did like were bits and pieces of the overarching story that could be found in these individual cases. The answers to the question of what happened 10 years ago that caused Li Lian Hua's world to collapse around him.

Other thing I loved were the characters, especially the 3 MLs. Their stories were complex and their relationship was so interesting.
Li Xiang Yi, the young genius and prodigy who stood at the top of martial arts world before he even turned 20, eager to prove himself, arrogant and stubborn, but also incredibly kind and righteous, turned into Li Lian Hua, a sickly wandering doctor who pretends not to know how to fight, who is sly and incredibly intelligent, but also aloof and distant. What I really enjoyed the most was the contrast between the two, and his attempts to hide his identity from the people from his past, from his girlfriend, his friends and his enemies. His attempts to hide his identity from Fang Duo Bing, who idolizes Li Xiang Yi and sees him as his master and doesn't believe he died 10 years ago. Even though in Li Lian Hua's mind, Li Xiang Yi was responsible for everything bad that happened 10 years ago, even though he blamed himself for all the deaths and the downfall of his own sect and he wanted to forget about Li Xiang Yi existence and let go of his past life, he couldn't completely distance himself from his old life. Every time we got a glimpse of old Li Xiang Yi my heart fluttered.

Cheng Yi who played Li Xiang Yi/Li Lian Hua was perfect for this role. He really managed to portray all sides of this complex character. His youthful arrogance, incredible martial arts skills, later jadedness, sorrow and sickness. The peace with which he accepted his own fate. He really knows how to play tragic characters.
I won't go too deep into other two characters, but I'll say that I loved their relationship with ML. Even Di Fei Sheng who at first shows up as an antagonist turns out to be very likable and his friendship with other two is so fun and full of ups and downs.
Fang Duo Bing's care for Li Lian Hua, who is battling with the poison for 10 years and seems like he doesn't care about his own life, was touching. Their confrontation after he finds out Li Lian Hua's real identity was also touching. The antagonism between him and Di Fei Sheng was fun, as was the rivalry between Di Fei Sheng and Li Xiang Yi. If nothing else, this drama is worth watching just for the relationship/bromance between these 3.

Another thing that this drama did well were action scenes. Fighting and sword dancing (really, can't use any other word for what Li Xiang Yi did with his sword) were amazing. All 3 MLs are incredible fighters and seeing them in action was amazing.

The music was good. It wasn't as memorable as in some other dramas, but it was adequate.

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The ending was also satisfying. All the bad guys got what they deserved, MLs managed to solve the mystery and save the world, and Li Lian Hua's fate was left open. Did he die or not? I don't know. They gave me just enough to feed my delusions so I believe he survived and managed to cure himself.