When Alicia and Devlin are riding their horses (and about to meet up with Sebastian), the shadow of the microphone boom can clearly be seen as it passes over Alicia's face when they ride out from under the trees.
When drunken Alicia is struggling with Devlin in her car at the beginning of the movie, after he causes her to pass out, Ingrid Bergman can be seen sliding over in the car seat to make room for Cary Grant.
When Devlin and Alicia are having a drink at an outside table in a busy cafe, the same portion of background film was used in two separate parts of their dialogue (a man walks away from the camera, then a waiter approaches a distant table and starts to put down some drinks from his tray).
After just arriving in Rio, Alicia and Devlin are drinking at a café. In one shot, Alicia is touching her glass which is still on the table. In the very next shot, she is removing the glass from her lips.
Did Hitch goof? At the dinner which Alicia Huberman (Ingrid Bergman) attends with all the I.G. Farben baddies, there seems to be an uncharacteristic slip-up for the usually meticulous and detailed oriented Hitchcock. The labeled bottles of wine "(Volnay) Cailleret Bouchard" that Emille Hubka (Eberhard Krumschmidt) is visibly disturbed about, bears totally NO resemblance to the later bottles of "Pommard," those down in the Sebastian wine cellar, where some specific ones contain the radioactive ore samples. For one thing, the earlier bottles have no separate vintage labels as do the 1934 bottles in question, and, even the bottle shape is wrong.
When Devlin and Alicia go to find Sebastian riding horses, there is a quick two second shot of all four characters next to each other on horses and two arms are visible walking the horses of Sebastian and the woman he is riding with.
Early in the movie, an intoxicated Alicia Huberman asks to go driving with T.R. Devlin. They are then seen driving in a 1941 Cadillac Series 62 Deluxe convertible in Miami Florida (top down). Current year of the movie is 1946. The 1941 Cadillac Series 62 Convertible is a rare model with only 3100 units built. Later in the movie, Alicia Huberman and T.R. Devlin fly to Brazil. Once in Rio de Janeiro Alicia and T.R. are again seen driving in a 1941 Cadillac Series 62 Convertible (top up) which would have been extremely rare in Brazil. Less then 500 were built for export. The same car is used in both scenes. This would have been impossible in real life as the flight would have taken hours to Rio where shipping the car would have taken weeks. Both Rio scenes and Miami scenes were shot in either country using the same car.