Arrow+The Flash!
The Flash has some science in it because the main characters are scientists and they use different scientific methods to find weaknesses in enemies. Basic plot is there is a kind of explosion from a partical accelerator and this caused people to have superpowers and a team are formed to stop the evil guys with superpowers. I just gave a basic plot because you'd probably wanna not have much spoiled. But if you do watch The Flash you gotta watch Arrow too because they both cross over a lot and The Flash originates in Arrow season 2. The order you should watch it in is:
Arrow Season 1---> Arrow Season 2---> Flash Season 1 Episode 1---> Arrow Season 3 Episode 1---> Flash Season 1 Episode 2---> Arrow Season 3 Episode 2---> Flash Season 1 Episode 3---> Arrow Season 3 Episode 3 etc.
Arrow is basically a guy who was stranded on an island for 5 years. He had one goal on that island which was to survive. He returns home and become this badass vigilante and kills anyone who commits major crimes and stuff. It gets quite intense and is an emotional joy ride.
As someone mentioned above Game of Thrones is good. Game of Thrones is an emotional joy ride aswell I assume if you do watch it you'd probably get quite sad and angry a lot. That could be said about some parts of Arrow and The Flash but Arrow and The Flash are PG so it wouldn't be as extreme and gorey as Game of Thrones is. But dude just watch all 3!