What are the scariest pieces of classical music?

That's the question for today, since this Music Friday happens to fall on Halloween.

Everyone knows Saint-Saëns's Danse Macabre:




And don't you love Mussorgsky's Night on Bald Mountain?




But have you heard the 2nd movement (Scherzo) of Bruckner's 9th Symphony, which starts out quietly creeping along but then suddenly bursts out into the classical equivalent of heavy metal?



(In case you couldn't tell, the conductor is Leonard Bernstein.)


And for absolutely bleak despair mixed with terror, nothing beats Shostakovich's 8th String Quartet, which he originally intended to serve as his own suicide note! And not a very subtle one, at that. (Fortunately, the only part of this plan he carried out was the music; he died of cancer many years later.)

1st and 2nd movements (it first gets scary at the beginning of the 2nd movement — around 4:45):



(This performance is by Students of the Royal Academy of Music in London: Alexandra Hjortswang, Beatrice Scaldini, Nicola Grant, Madeleine Ridd.)

3rd movement:



4th and 5th movements (notice how the end of the last movements recalls the beginning of the first movement):



Had enough?

If not, then feel free to suggest some more in the comments!

UPDATE: See the comments on the post you're reading now and also the 60-odd comments on this other post for suggestions.