BBC:
Killing Eve
Fleabag
Peaky blinders
Giri / Haji (quirky Anglo - Japanese contemporary gangster thing. Very good)
Netflix:
Breaking Bad (if not seen you'll have heard about it. Worth the hype) if you like that, the prequel is:
Better Call Saul
After Life
Fargo (series based loosely on the Coen Brothers film. Quirky, violent, epic. Some British actors)
Narcos
Narcos Mexico
Bloodline
Tell me who I am
Don't **** with cats
Confession killer
Sky/ Hbo:
Gomorrah (this is the #1 of the lot IMHO. Italian Neapolitan crime family drama series. "epic" dies not do it justice. Brutal, shocking, hyper - real. All the romance of the Godfather et Al completely absent. TV drama on another level). And if you like that there's:
Suburrah, Blood On Rome (same director as Gomorrah. Very similar. But that's on Netflix)
The Bridge (scandi - noir at its best)
Chernobyl
Westworld
The Wire (try subtitles for a bit if the street slang gets too much)
Boardwalk Empire (Steve Buscemi brilliant as 20s gangster and Steven Graham as a young Al Capone. Scorcese was involved)
.. And I'll second that Deutschland 83 someone mentioned. Can't remember where it's on. C4 maybe?
Should keep u goin a while that lot.