Joaquin Phoenix seems to fully inhabit the character of Arthur Fleck, a none-too-successful professional clown who spirals downward into mental illness hell to become one of the memorable villains of the Batman universe.  Alas, his performance is not enough to save us the slog of travelling the long and tortured path a viewer must take to get to the gripping part of this unrelentingly bleak film.  Unfortunately that part is only the last 20 to 30 minutes of a movie that lasts over two hours.  Kudos to Joaquin (although the late Heath Ledger is by far my favourite Joker) for his obvious talent, but such talent cannot by itself hold a troubled film together.

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