YMMV / Sherlock S4 E2 "The Lying Detective"

• Complete Monster: Culverton Smith is a seemingly charitable philanthropist who uses his public persona to hide the truth that he is a sadistic Serial Killer whose greatest desire is to kill anyone he can. Having taken part in the construction of a hospital, Culverton secretly outfitted it with a variety of secret passageways and doors, which he uses to enter the rooms of patients and murder them, framing their deaths as accidents or natural causes so as to enable his murder spree to go on for years and claim countless lives. Spending his free time playing with corpses in the hospital's mortuary and drugging people so as to confess his crimes and enjoy their horrified reactions before the drugs wipe their memory of the confession, Culverton taunts Sherlock and Watson with his crimes when they begin investigating him, before ultimately trying to kill Sherlock with obvious sexual glee. Boasting the simple motivation that he just loves to watch people die and make them into "things" for him to toy with, Culverton cheerfully confesses to his immense amount of murders when caught, musing about how famous he's going to be for the killings.
• Moral Event Horizon: Culverton Smith pretty much on everything he does considering he wants to kill just for the sake of wanting to murder "anybody" all while using his wealth and power to avoid getting caught.
• Shocking Moments: Nobody saw that the third Holmes sibling would be a woman, let alone the true Big Bad of Series Four.
• They Wasted a Perfectly Good Plot: We learn that Eurus has been posing as John's therapist; she was also the woman he'd been having a text-based affair with, and they met face to face then at least once. The following episode reveals that, unless you're a supergenius like Mycroft and Sherlock, she can implant orders into your mind just by talking to you. You'd think this would be set-up for her having some control over John. Nope!

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