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Sorry I don't know - but it's a cracker. My colleague, who I name my Dexter-dealer brings them in on a memory stick every monday after they're aired in USA. Season has just finished and is soooo goooood. Bumping for someone more helpful to come along
Can't find anything at all about when this is due to be broadcast in the UK. Nothing on FX website, and I'm avoiding googling to find out as there are spoilers out there and I don't want to know what happened!