Factual error: When Willie is taken from the hospital to appear in a criminal lineup, he is wearing a special watch he received for his birthday. When you are admitted into the hospital, the first thing you have to remove is a watch and/or jewelry.
Plot hole: Genius Henry amassed $680K plus "more" in stocks and bonds. The amount seems way too high for an 11-year-old, who undoubtedly didn't start investing as a toddler. Throw in the adage "you have to have money to make money" and the figure is unrealistic. Even IF Susan earned $15 per hour minimum wage (tips included) waitressing at a quaint Hildebrandt's soda shop, $31,200 annually before taxes doesn't go far for a family of three in NY. Would there be ANY discretionary income for Henry to use?
Factual error: The black leather chair of the Home trust banker is more modern than the movie setting in 1922. (00:59:35)
Visible crew/equipment: When Detective Hole enters the murderer's cabin you can see somebody running in the snow outside.
Continuity mistake: Maggie gets downstairs while Henry and her daughter are playing with their phones. The hair goes in front and behind her right shoulder depending on the camera angle. (00:03:00)
Continuity mistake: Michele Riondino has just killed the snitch and is going after the witness, a Chinese woman. He holds her at gunpoint; she does not move, but in a shot she has hair in front of just her left shoulder, both shoulders in the next. (00:30:30)
Continuity mistake: Gardner Lodge first takes a bite from the corner of the peanut butter and jelly sandwich and sets it back on the plate. The camera angle changes and when he is seen holding the sandwich again the bite is now taken from the middle of the sandwich. (01:28:55)