The night she disappeared by April Henry

Imagine that someone you work with vanishes without a trace, and then you find out that the person who took her really was targeting you instead!
That's what happens to high school student Gabie, who works part time at a pizza place. Another girl who works there, Kayla, asked if Gabie would switch shifts with her, and so Kayla was working on the night that John Robertson orders three Meat Monsters using a fictitious name, address and phone number. Kayla never comes back from delivering the pizzas, so now Gabie and Drew, another pizza place employee, are doing their best to figure out who took Kayla. The story is told from multiple perspectives, including Gabie, Drew, Kayla and John's viewpoints. You know who is narrating the story because they get their own chapter, and the chapter heading contains their name.
Good thriller without being too disturbing.

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