One of the greatest movies of the 20th century is about a man who magically turns into a dog. I'm not talking about The Shaggy Dog or its remake starring Tim Allen. No, I'm referring to the greatest hidden gem Disney+ has to offer, The Shaggy D.A. As the title so cleverly suggests, it is a movie about a man who is running for District Attorney and can't stop turning into a big white fluffy dog . The best part of this movie is its action sequences. If you haven't seen the viral clip where a man…