I'm fluent in (Mexican) Spanish. The Colombian accent is a little tricky for me and they use a lot of crazy slang on that show so the subtitles help but you pick up a lot more from the dialogue in Spanish than from the (sometimes poorly translated) subtitles!
Narcos, it's a show about Pablo Escobar. It's on netflix and I highly recommend it.
My girlfriend watched this whole show in about 2 weeks, I'll have to catch up on it.
Great show, but be aware that you will spend 70% of the time reading the subtitles as most of the show is in Spanish.
I'm fluent in (Mexican) Spanish. The Colombian accent is a little tricky for me and they use a lot of crazy slang on that show so the subtitles help but you pick up a lot more from the dialogue in Spanish than from the (sometimes poorly translated) subtitles!