I'm watching the series right now. Got the trial subscription. I'll cancel it before I have to pay, of course. I've already got Netflix and Amazon prime, I ain't buying a third.
That said, this series is really good. The middle-aged, washed up former villain from the "Karate Kid" movies sees a kid getting picked on by 6 guys. He beats the shit of them without even trying, and the kid he saved becomes his student. He teaches the kid some moves, and the kid tries to beat up the bullies just like his teacher. There's only one problem: his teacher is a fucking action-movie-villain. An action movie villain, even a tired aging action movie villain, can take on six guys and beat their asses. A regular person can't do that shit. So the kid gets beat up and now the former villain has to deal with all the complicated repercussions.
Basically it's a drama about what happens after the credits roll on something like "The Karate-Kid".