Vincent doesn't panic, doesn't beg or anything just has a look of "I made a mistake" and dies

Moment at 0:00 in Not a single word was spoken here. | Pulp Fiction (1994) #shorts by gabri192.

In the movie, there a subtle things to show what led to this. First is Vincent’s addiction to heroin. One of the side effects of heroin is constipation. This obviously isn’t the first time we see Vincent having to go to the bathroom. If he’s constantly feeling like he has to take a shit but also can’t, then that’s going to take up some of his time. The second part of this from the rest of the movie is his carelessness shown throughout the movie. When we first see Jules and Vincent pull up to confront Marvin, you subtly notice Jules put his safety on, while Vincent does not. While this isn’t always a big indicator of careless, it’s followed by his lack of trigger discipline when he accidentally kills Marvin. Basically the fact that he would need to use the toilet when he’s about to kill someone, combined with the idea he would leave his firearm away from himself with a door closed are things you could see coming.

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