It means he went away from the main group to come up with a plan to solve the problem/conflict. I believe he will use magic to (I don't know what the conflict is, but this is where you'd put how you think he'd fix it)
The answer is: 3. It helps establish the idea that Didion's experiences in New York feel somewhat surreal to her now, like those of a character in a movie. <span> </span>