Other mistake: During the big chase scene, a car hits a camera right after it passes a blue '68 GTO.
Other mistake: Just before the Charger crashes, a tow bar connecting both vehicles is visible on the Mustang's front bumper.
Other mistake: When we get a front shot of the two cars jumping the hills, watch when the Mustang lands on all four wheels. It gives out a tremendous amount of smoke and steam from underneath. (Slow it down on DVD for the full effect.) This is because the car landed too heavily and shattered the sump (oil pan). The other Mustang had to be used while the mechanics repaired the damage.
Answer: The man shot at the hotel at the beginning is Renick. Ross assumed Renick's identity and was going to flee the country. Ross kills Mrs. Renick to keep her quiet. The man at the airport that Bullitt kills is Ross.
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