Continuity mistake: Once Rose has put up the Union Jack flag, Charlie tells her "You'll wait for me on the East shore." The sentence is across two shots, the second part remarkably pronounced with a big cigar between Mr. Bogart's lips. It just was not there before. (01:31:15)
Revealing mistake: As Charlie holds Rose close and tells her that "We'll never lack stories to tell our grandchildren" after the assault of the bug swarm, the background is perfectly in focus, but the engine behind them is not - on top of showing chromakey white noise in the top right corner. (01:13:35)
Continuity mistake: Rose offers Charlie to help with the propeller. He says "Here goes" and motions to go back underwater. Katharine Hepburn's hands are on the vertical supports sticking out. Not a moment has passed (you hear the plop of him actually submerging) and in this new reverse shot her hands are by those same supports, not on them. (01:07:15)
Revealing mistake: During the crossing of the rapids, in several shots you can see a white (possibly green if you are looking at a video version that came out before the 2009 restoration) halo around the actors, in particular the hat and hair. (00:38:15 - 00:39:05)
Revealing mistake: The Germans burn the whole village and deport the natives...who don't seem all that concerned. You can spot some being rather casual about it, and smile as they get herded away - like the woman in the blue dress. (00:12:40)
Continuity mistake: After crossing the first rapids, Humphrey Bogart's shirt appears to be mostly wet in the back. When he talks to Miss Sayer, it's the front of it soaking wet. (00:39:15)
Visible crew/equipment: Look closely the bottom of the screen when Rose screams seeing the leeches on Charlie: some black piece of equipment (it's not a stain on film or lens) pops up slightly and hovers a little before going out of frame again. (01:17:50)
Revealing mistake: In the execution, the noose is so loose that Bogart's head virtually pops out of it, even as the sailors in charge of the execution have already begun pulling the rope. (01:42:35)
