Visible crew/equipment: When Dickie and Ripley are scootering down a little Italian hillside, you can see the shadow of the whole film crew against the hill.
Visible crew/equipment: When Dickie, Tom and Marge are coming out of the Venice Railway Station via revolving glass doors, the cameraman is visible in its reflection on their left when it closes.
Chosen answer: Tom & his lover are travelling on a boat. The rich girl, who knows Tom as Dickie is also on the boat. If they were to meet, Tom's false identity would have been revealed, and the lover would have been able to figure out that Tom actually murdered Dickie.
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