When Jaques Gambrelli leaves the hospital, his bike has wet cement on the wheels. In the next scene, the wheels are clean, with no trace of cement.
When Jacques and Yasmin are reciting from Romeo and Juliet, Yasmin puts her hand on Jacques face. In the next shot, her hand is nowhere on his face but goes back to being on his face in the shot after.
Robert Davi sets fire to a fishing boat, dives over the side and swims to a yacht and when he's seen on board he's dry.
Early on in the film 4 frogmen dive from a fishing boat and swim under water to a yacht which they board and their suits are dry.
Commissioner Dreyfus' non-recognition of Maria Gambrelli during the encounter at the Gambrelli home. Dreyfus considered Gambrelli a prime murder suspect in A Shot in the Dark (1964), but she looks different (in fact, this is probably a joke on the fact she's played by a different actress).
When Commisioner Dreyfus accidentally ejects himself from his hospital bed, person being ejected is a clearly a stunt double, with darker hair, and more of it.
When Dreyfuss discovers he is standing in shallow water, his clothes are wet and become partially see-through. Because of this, it's obvious he is wearing a wetsuit under his clothes. It's the same kind of scuba suit used earlier in the film.
The bomb planted outside of the Gambrelli house is set to detonate within four minutes, but it only takes 48 seconds in the film for the bomb to explode - not that it's in real time and it would take that quick for four minutes to go by so quickly.
Gambrelli says "ha" when Yussa shoots at him, but his mouth is closed.
When Gambrelli and Cato are in the Lugash airport, one of the assassins on the walkie talkie has a pair of dark sunglasses that reflects the film camera and possibly a white light.
There is a shot of Istanbul featuring Hagia Sophia. However, not one scene of the movie takes place in Istanbul or Turkey and not one character is Turkish.