I've just watched Tiger King on Netflix and I have to say its absolutely bonkers, only in America, had me captivated all the way through.
https://www.netflix.com/gb/title/81115994
For more unbelievable but true stories 'The Jinx' is on most platforms (sky for free) and is fantastic, I binged watched that a few years ago and its just coming to a head now with I'm sure more HBO episodes in the pipeline:
https://www.rottentomatoes.com/tv/the_jinx_the_life_and_deaths_of_robert_durst/s01
But the undisputed TV series, and still unsurpassed in my book, The Sopranos - tremendous, watched it all the way through 3 times and still picking up on new bits.