Goofs[1] for

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Charlie Chan in the Secret Service:

Revealing mistakes: Much is made over the fact that Dr. Melton, the murder victim, was left-handed. Yet, earlier, he was seen doing various things, such as taking notes, opening a door, and turning on the fatal light switch, all with his right hand.

• Errors in geography: While we are supposed to be in Washington DC, when Charlie Chan leaves the office building you see the California state flag outside.
• Errors in geography: Also, while Charlie is riding in a cab to the murdered doctor's house in "Washington, DC", he goes through a neighborhood full of houses with red tile roofs and palm trees in the yard!

>>> WARNING: Here Be Spoilers <<<

Goofs below here contain information that may give away important plot points. You may not want to read any further if you've not already seen this title.

• Continuity: SPOILER: Paul Arranto, the wheelchair-bound suspect, is shown standing with the rest of the suspects around the piano when Vom[2] Vegan is murdered, well before Chan reveals that he can indeed walk.
  

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