BBC’s Sherlock made sure to include Jim Moriarty, Sherlock Holmes’ archenemy, who brought a lot of trouble in seasons 1 and 2 – but why was he so obsessed with Sherlock? The Great Detective made his debut in A Study In Scarlet in 1887 and has since been one of the most popular characters in literature and pop culture in general, as he has been adapted to other media – stage, TV, film, video games, comic books, and more – for over 100 years.

One of the most recent (and well-received) adaptations is the BBC’s Sherlock, starring Benedict Cumberbatch as Sherlock Holmes and Martin Freeman as Dr. John Watson. Set in modern-day London, Sherlock brought some of the detective’s most famous cases to the present day, adapting them to modern technologies and more, and it also included some of Arthur Conan Doyle’s most memorable characters, such as Irene Adler and James Moriarty. As Sherlock’s biggest enemy, Moriarty (played by Andrew Scott) brought a lot of trouble, but he reached a point where he was obsessed with the Great Detective.

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Moriarty was the “consulting criminal” to Sherlock’s “consulting detective”, and was one of the few people whose intelligence was at Sherlock’s level. Just like the famous detective is in the books, Moriarty was a great actor and managed to fool a lot of people with a dangerous mix of acting and blackmailing. He was manipulative and was the mastermind behind many, many crimes in London, and even gave advice to Irene Adler on how to manipulate the Holmes brothers. Moriarty’s obsession with Sherlock peaked when he came up with a very elaborate plan to bring Sherlock down and destroy his reputation, which began with simultaneously breaking into the Tower of London, HMP Pentonville, and the Bank of England, and then turning himself in.

Moriarty in Sherlock

Just like Sherlock’s, Moriarty’s mind was very complex, and he got his kicks from all types of weird and dangerous things – and at one point, he pondered suicide because he was bored with the world. His obsession with Sherlock Holmes was rooted in how, as mentioned above, he’s the only one at his same level of genius, thus representing a challenge to him: he made up all types of crimes and riddles, and then sat back to watch how Sherlock solved them. Moriarty’s interest in Sherlock came to an abrupt end when he realized they were more alike than he thought, as the detective also had a dark side, and decided to kill himself on the spot so Sherlock had no other choice than commit suicide in order to save his friends.

Many fans have debated whether Sherlock was equally obsessed with Moriarty or not, only that he demonstrated it differently. Although Moriarty did bring a lot of trouble to Sherlock in the books, he wasn’t obsessed with him as he was in Sherlock, instead just being an evil genius looking for revenge against the only person that was at his level. Moriarty’s obsession in the series worked well, and it helped the storylines moved forward while also giving his relationship with Sherlock a disturbing touch.

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