Just got back from the movie. Interesting, they never depict the Swimmer inside the car from the moment that it enters the bridge area. Plenty of footage of him outside the car, though, around the pond and sunk/overturned car. Many views of various personages with futility pulling on the door handles. It's as if perhaps the movie writers implicitly thinking there may be truth to him not being in the car during its plunge; at least not "pouring water" on the idea.
Were there many there?
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