In my country all TV programmers non-natives have subtitles, when I'm in Portugal I turn on the TV I choose any channel and voilá I've subtitles I just need choise some movie, serie or programmer I like so it's hard recommend you but I can let you here some of my favourite series if you don't mind :) If you want also some movies tell me I can suggest you some of them.

Series: Shameless US, Roma, Tudors, Spartacus, Skins Uk, Vikings, Teen Wolf, Supernatural...

Castle would be my first choice, too, they speak very clearly.

I'll try to cover different genres and series that are popular enough to find:

- In Vampire diaries they speak clearly, too.
- The Good wife. They speak a bit fast, but it's very good for vocabulary and structure.
- Sirens and Brooklyn Nine-Nine for contemporary language and because they are 20 min. episodes, you won't get tired and you can squeeze an episode in a study break.

Hope this helps!

I suggest you watch Canadian ones, they speak really clearly. You can watch them without subtitles, which is useful if you want to develop your listening skills. I like Castle, Murdoch Mysteries and Motive.

In my opinion, the best way would be watching either a movie or a TV serie episode which you have already seen more than once. As you already know what is going to happen next, you can focus on the language. 

But choose something you do enjoy watching, this way it will not be a problem to watch over and over again.

I usually watch "once upon a time" with english subtitles. I think that it is a good way to understand language :).