There’s a sense that something is lacking, or perhaps several things are absent. Jack Black portrays Jan Lewan, the quirky and endearing Polka King of Pennsylvania. He possesses unwavering confidence in his abilities and an intense desire for widespread recognition. However, he isn't particularly bright, and his music doesn't resonate with many people beyond a devoted group of older fans. Driven by what appears to be generosity, he initiates a scheme resembling a Ponzi scheme to ensure his musicians are better compensated and expand his operation. Jack Black delivers a decent performance; therefore, those who appreciate his comedic style or Polka music might find something to enjoy here. Otherwise, it seems the cast perceives this as a comedy when there’s little actual humor present in what's shown or said. The movie progresses at a leisurely pace, depicting real-life occurrences, but fails to capture any of the genuine emotion or depth that would have come from portraying the true individuals involved. The biggest letdown was Jason Schwartzman; the typically reliable comedy actor seemed to be simply going through the motions. And JB Smoove's presence felt like a complete waste. Jenny Slate appeared to be the most invested in her part, aside from Jack Black, but even she couldn’t salvage this film. Overall, the movie brought to mind another true-life story featuring Jack Black, "Bernie," and “Bernie” was better in every respect.

Source on TMDB