There was a song that I heard called That's Entertainment. I heard it years ago when I was a kid and for some reason I had a moment of childhood nostalgia when Lady Gaga sang it in this movie. There isn't much else nostalgic or light hearted about this film it is as dark maybe even darker then the first. Joaquin Phoenix returns as the tormented and pathetic Arthur Fleck. He has been cooling his heels in Arkham Asylum for two years awaiting trial for the murders he commited as the Joker. He falls in love with Harley Quinn (Harlequin is another word for clown). She seems to be as disturbed as he is and the title of this film is a medical term for two people with a shared insanity. I couldn't believe that they actually made this film a musical but Phoenix and Gaga do a good job. The musical numbers range from beautiful to sick humor (where he bashes the judge's head in). The trial is played out before the media like so many today and it is so pathetic when Fleck represents himself and in the end in a shattering closing argument he denounces his Joker persona and admits he lives in a fantasy world and in real life he is just this pathetic, disturbed child man. Phoenix does a haunting job acting often with only his pained, or crazed facial expressions and Lady Gaga shows she can act as well. In the end, you don't like these two people or care what happens to them and you are torn between almost feeling sorry for them and being disgusted by them. SPOILER ALERT It looks like Fleck is dead in the end when that other inmate "does a Dahmer" on him but who knows big box office returns have amazing powers of revival.