10. Hans Schroeder
He didn't survive past the pilot, but Margaret's boorish, abusive husband led her directly into the cyclone that is life with Nucky Thompson. The black eye on a heavily pregnant Margaret's face doesn't go unnoticed by Nucky when she first beseeches him for financial assistance. The big wad of cash she comes home with that day doesn't go unnoticed by Hans, either. After Hans' latest beating causes Margaret to miscarry and puts her in the hospital, Nucky, unable to ignore his fascination with this sad-eyed Irish woman, flexes his gangster muscles for the first time in the series by making Hans sleep with the fishes (he's discovered in a fishing net along with the catch of the day). Her dangerous husband eliminated, Margaret embarks on a far more dangerous relationship in the coming episodes and seasons – with Nucky Thompson himself.