What are your fav unresolved mysteries or conspiracies?

What are some of your guys' favourite unresolved mysteries or conspiracies, aside from the obvious (the sugar bowl).

Mine is Captain Widdershins disappearance - the Baudelaire's return from the gorgonian grotto and it's almost as if he's disappeared from the face of the earth... I remember agonising over it as a kid lmao.

Wish it was included in the Netflix adaptation!