It is must watch because all those works that we have seen until now seem so little in terms of their emotional intensity before this masterpiece of a thriller. For anyone out there with similar tastes, this is a must watch content.
I have been a huge fan of crime dramas of Martin Scorcese and thrillers of Alfred Hitchcock and totally enjoy movies that dive deep into human emotions such as 7even, Taxi Driver, V for Vendetta, Machinist, Schindler's List, American Beauty etc. This is not typical anime, it is not even a series or a video, it is an experience I have gone through watching this piece of brilliance called Monster.