Stephen Georg’s review published on Letterboxd :
Shot as a mockumentary (but based on a true story!), Bernie is the tale of an assistant funeral director who befriends then later kills a millionaire widow. Small-town Texas sets the stage for one of the best black comedies I've ever seen.
What sells the film are the actors—and not just one. Every single role. Every single person in this film is perfect. Jack Black plays the protagonist, Bernie, and knocks it out of the park. In fact, this might be the best and most convincing role I've ever seen him play. MacLaine and McConaughey are amazing as well, but I'd hand out awards to those who played the townspeople. There were several dozen roles (since this is shot in documentary format) and everyone completely nails it. What's mind-blowing is that only about half of the townspeople are acting—some are actors, but others are actually from Carthage, TX, and know the story personally. You will not be able to tell the difference.
I believe the eccentricities of the small-town Texans strike a chord with me, and is partially why I enjoyed the film so much. As someone who has spent their life in the south, I know these personalities and accents and phrases personally, so the film felt especially authentic. To me, nobody was acting, and that feeling (coupled with it being based on a true story) really brought Bernie to life.
Recommendation? Absolutely. Even if you don't connect to the "small southern town" residents like I did, you'll still appreciate the wildly colorful characters. And I can't undermine how incredible Jack Black's performance was—I mean, he was Bernie. Everything about this film is fantastic, and my only regret was that I didn't watch it sooner.