Billions was very good right up til the end of Season 3 iirc. Sometime soon after
, the show went from good to just totally unwatchable imo.
Age of Samurai is very interesting and well done, but it didn't hook me hard because I'm neither patient enough nor smart enough to binge a history show. I'm sure I'll return to it but I'm only through 3 eps right now.
Zerozerozero was mentioned earlier in this thread; I highly recommend it. My only real complaint is that the character development was limited. All in all, it's a stunning series with lots of action, great acting, a huge geographical scope, and tons of suspense.