Defiantly Game of thrones! What a thrilling series!
I really like
The Walking Dead series is simply amazing
Waiting impatiently for season 8
Rick and Morty, Steven Universe, Star Wars The Clone Wars, Alanta, Breaking Bad, The Wire, etc.
My current best TV show is Silicon Valley. I saw, by accident, the last two episodes on cable while in a hospital. Prior to that I had no idea about the series, but I immediately got hooked. Season three is about the new internet the lead character Richard Hendricks is developing. That got me interested in blockchain and decentralized internet technology like Interplanetary File System and Blockstack.
Breaking Bad of course! And its prequel: Better Call Saul, can't wait for the next season!
If you are into comedy The Big Bang Theory, or any of Chuck Lorre's creations (Young Sheldon, Mom, Two and Half Men...), but obviously Britain rocks here, nothing beats Fawlty Towers and the like.
Love the 80s? Go with The Americans or Deutschland 1983
If you are into crime, Dexter and The Shield are really good.
Are you a geek? You can't go wrong with Black Mirror or Mr Robot
Politics? House of Card, Veep, The Thick of It, funny as hell!
Talking about hell, Lucifer and also The Good Place are not bad.
13 Reasons Why,
The Walking Dead,