Baccano!
There is not a single writer on this planet who I think can match Narita, when it comes to writing this kind of story -with a (really really) large ensemble cast and multiple interlinked story arcs- and Baccano (and later also Durarara) is perfect proof for that.
Each and every character is phenomenal, I love the setting and while it has visually aged a bit poorly in few scenes I still enjoy the score and unique art style.
I’m still not the biggest fan of those last 3 OVA episode hence „only“ 4.5 stars.