No longer in the UK and I was looking in the wiki .
Result , reason it's not listed on normal site where I watch them ....is oz it aint been shown in uk yet.
Moved to Switzerland 8 weeks ago and subscribed yo FOX HD cable channel and it's a German version and don't show DEXTER ....FAIL ! lol
Try online, type in Dexter and a few sites should show up, you will have to sort through a lot of stuff before you find it but I'm pretty sure you will be able to find it. My daughter does this a lot to find American shows she likes and is generally able to watch pretty much what she's looking for online. Try a site called "Dailymotion" to start with and type in the name of the show when you get there. Happy hunting