When Commissioner Renard tells Vance Colby the names of the witnesses to his father's death, Vance writes the names on a card - the 3 of spades - having no other paper on him. As each man dies, Vance tears of a piece and tosses it away. When the last of the three (Rivage) dies in a duel with Vance and falls into the river, Vance tosses the card remnant after him. As it floats by, it is no longer a 3 but an ace of spades, which, according to ancient legend, is the symbol of death.
Dale Robertson long stated this was his favorite of his movies.