Nonsense plot

Rating: 1/10 (12 October 2019)

Arthur Fleck lives with his invalid mother. He is suffering from mental illness possibly as a result of childhood abuse. Budget cutbacks put an end to his weekly counselling sessions and he goes off his meds. In real life anyone else would quickly become non functioning but he seemingly becomes more normal.
Consequently he goes from being a bumbling idiot to a highly skilled criminal. I didn't find that realistic at all. He also starts a hardly believable relationship with his beautiful single mom neighbor.
It turns out that was in his imagination but the way it was portrayed made it impossible to tell which scenes were real and which imagined. The scenes with Robert De Niro seem like fantasy but apparently are real.
There were many other scenes that defied belief:
A random work colleague gave him a loaded handgun for free out of concern for his safety. Same person tried to throw him under a bus at the first sign of trouble.
His neighbour left her door unlocked despite the dangerous neighbourhood.
He was a suspect in multiple murders yet the cops made little effort to detain him.
When he kills his mom in the hospital her ECG doesn't sound an alarm and nobody suspected it was him.
Etc.
Towards the end of the movie they recreated a scene from the Dark Knight which reminded me that Heath Ledger was 100 times better.
I cannot see how the Joker portrayed in this movie could possibly become the Joker we know.