[quote=@Delta44]
[@Daxam] Just added it to my massive anime list! Though I put it near the top so it'll get viewed quickly!
[/quote]

You'll know when it gets into the dark half when the outro music changes. It goes from the usual, soft, wind-down music to some pretty dark and heavy music. It's so great X3

Trigun and Cowboy Bebop, too. They could be considered starting off rather light-hearted and jokey, but then they get very serious toward the end. They're also two of my favorite shows ^^

And, although I don't know much about it, try Higurashi: When They Cry. It gets incredibly dark at some point, that much I do know