Joey King

Wren

Julia Goldani Telles

Hallie

Jaz Sinclair

Chloe

Annalise Basso

Katie

Alex Fitzalan

Tom

Taylor Richardson

Lizzie

Javier Botet

Slender Man

Jessica Blank

Hallie's Mom

Michael Reilly Burke

Hallie's Dad

Kevin Chapman

Mr. Jensen

Miguel Nascimento

Kyle

Eddie Frateschi

Biology Teacher

Oscar Wahlberg

Boy with Glasses

Danny Beaton

Burley Kid

Marc Carver

Doctor

Kris Sidberry

Librarian

Angela Hope Smith

Nurse

Damon D'Amico Jr.

Student

Timothy Brierley

Tour Guide

Kayla Caulfield

High School Student (uncredited)

Jeffrey Corazzini

Police Officer (uncredited)

Michael Tow

Calculus Teacher (uncredited)

Adrian M. Mompoint

Jock (uncredited)

Kieran Tuomey

Student (uncredited)

Gabrielle Lorthe

Cheerleader (uncredited)

Yohanna Perez

Student (uncredited)