Maréchal falls in the sea backwards, but in the next shot he is clearly falling frontwards.
When Maréchal gets out of the shower early in his Italian trip, he is heard humming but the sound does not match his facial expressions at all.
In the movie, the location of the parking spot where the Cadillac's battery is dumped into the sea, is along the coast between Pisa and the French border. But the scene is filmed in Torre Capovento, a long way back south, just north of Naples.
Dan Vadis is listed as being in the cast and it NOT Dan Vadis.