In Raiders of the Lost Ark , the fight scene between Indiana Jones and the Nazi mechanic benefited from some improvements suggested by Harrison Ford.
Finding the fight a little too wise, and arguing that Indiana Jones was the type to allow himself all possible moves to win in such an unequal fight, the actor managed to convince Spielberg to add three “dirty moves” to the fight.
The first was to throw sand in the Nazi’s face to blind him.
The second was to bite him on the arm!
Spielberg thought this was somewhat undignified of Indiana Jones, but he was eventually convinced.
It is interesting to note that most of this sequence, which took 3 days to shoot, was improvised by Spielberg on set.
The death of the mechanic, cut by the propeller, was not planned in the script and was imagined at the last minute!
It remains to this day the director’s favorite scene in this film, and a true masterpiece of direction and inventiveness.