Goofs

The Venus statue and its silver stand sit on a green marble plinth throughout the film. After the statue is stolen and the guard points at the replacement bottle, the zoomed-in shot has the bottle on a white marble plinth.

When Nicole tells her father she drove Simon home, he spits back some champagne into his glass, then hands it half full to her. In the next shot, when they walk to the chairs, the glass is nearly full.

After Simon examines the statue using his glasses with loupes, he and Nicole walk away while he still wears them. In the opposing shot, he is holding them in his right hand.

When Simon replaced the Venus with the wine bottle, he placed the bottle near the edge of the green plinth, but when the guard is pointing at the bottle, it is in the center of the plinth.

Just after the Cellini Venus has been collected from M. Bonnet's Parisian mansion, Nicole and her father move to the salon and are discussing the tests to detect forgeries, and M. Bonnet says to Nicole, "the basic trouble with you is that you're honest". As he leans over to her on the sofa, the cigarette he is holding changes from his right hand to his left hand.

When Bonnet gives the curator the statue, the curator touches the white marble with his bare hands. A real curator would never touch a marble work of art with bare hands, as the oils from the skin can stain the marble, turning it yellow. Curators always wear white gloves before touching any work of art.

When the director of the museum chatters about the security system guarding the sculpture, he boasts about the infrared circuit. However, they're depicted as blue orb-like emitters and sensors. This is incorrect owing to infrared being on the opposite end of the colour spectrum from blue. If they truly were infrared emitters, they'd have a red tint to them.

The alarm in the museum is disabled after it is set off the second time by Simon, who then later on places a wine bottle on the plinth in place of the statuette.

Later, when one of the guards removes the bottle, the alarm is triggered again. However, it was never turned back on (and there would have been no reason to either, considering it was still believed to be faulty).

When Nicole with Simon are hidden in fireplace and visitors leaving museum accompanied by all guards (seen in mirror) right before they move to cleaning room, there are two moments when shadow of filming crew appear in base of right column beside fireplace.

After shooting Simon, Nicole drives him to the Ritz on the Place Vendôme. They arrive on the place François-Ier from the François-Ier street. This means they are going in the opposite direction, away from the Place Vendôme. Then, from the Place François-Ier, they take the Jean Goujon street, which means they are now on the right way. However, it would have been faster to turn back through François-Ier street.

Dermott makes a point early in the film to have Nicole wipe his fingerprints off the frame of her father's forged Van Gogh, which he's handled without gloves. But later, he barehandedly substitutes a wine bottle for the statuette he's just purloined. The Head Guard later has a minion remove that piece of evidence, likewise barehanded.

As Dermott is getting the key from the wall, it can be seen that the corner of the two walls is capped with raised molding, making it impossible to get by with just a magnet. This is why the scene breaks away, and when it returns, the key is on the other wall.

When the chief guard turns off the alarm, the sensible thing to do would have been to post a guard in the statue room to watch the Venus since the electric alarm was now off. There were plenty of idle guards available. That would have stymied the robbery.

When Nicole and Simon are in the bar at the Ritz, Simon orders "Scotch", and Nicole says, "Likewise". When the waiter brings the drinks, they are not the same color.