Sherlock: 10 Worst Things Sherlock Holmes Ever Did

This one is pretty self-explanatory, as while he certainly deserved to be taken down, killing this man in cold blood was a sudden and shocking act that proved the statement "I'm not a hero".

While it made perfect sense for Sherlock to use extreme force to end Magnussen's reign of terror, the lack of concern or remorse after killing him was terrifying.

The third season of Sherlock was a tough sell, as the show had lost its primary antagonist in Jim Moriarty and needed to bring in a whole new threat. Sherlock's writers did a decent job in this by generating the season's new overarching villain in the form of master blackmailer Charles Magnussen. But no one could have predicted how he'd be taken down.

After Sherlock and Watson came face to face with the villain and attempted to retrieve vital documents - some of which involved John and Mary - they found themselves backed into a corner. To get out of this, Sherlock took up a gun and shot Magnussen in the head at point-blank range.

It's true that, as the villain, he needed to be stopped. Still, seeing the protagonist commit murder was a particularly dark moment in Sherlock's life, especially as it didn't seem to affect him much afterwards.