Films or TV shows that have an unlikeable main protagonist?

[Volcano Grrl (aka Emby)]

I'm interested in films or TV shows that have an unlikeable main protagonist or at least leading character. One that perhaps the viewer might root for (like an anti-hero) but is utterley hateful in their actions, I can only think of the character Johnny from Mike Leigh's film Naked and Combo from This Is England and the This Is England '86 TV series (though he redeems himself at the end).

Can anyone suggest or recommend more? Any that change (for the better) at the end to make us question our previous viewpoint would be helpful.

Thanks in advance.
I LOVE Dexter but think he is ultimately likeable. He is what he is because he's serving justice and has a moral code by which he lives. I want characters who are utterley dispicable and sickening!