Jack Black as R.L. Stine

Dylan Minnette as Zach Cooper

Odeya Rush as Hannah Fairchild

Amy Ryan as Gale Cooper

Ryan Lee as Champ

Jillian Bell as Lorraine Conyers

Halston Sage as Taylor

Ken Marino as Coach Carr

Timothy Simons as Officer Stevens

Amanda Lund as Officer Brooks

Steven Krueger as Davidson

Keith Arthur Bolden as Principal Garrison

Karan Soni as Mr. Rooney

R.L. Stine as Hallway Player

Caleb Emery as Dumb Jock

Gabriela Hernandez as Screaming Girl

Nate Andrade as Monster

Sheldon Brown as Monster

Melissa Brewer as Monster

Marshall Choka as Monster

Melissa Cowan as Monster

John Deifer as Monster

Everett Dixon as Monster

Brian Gabriel as Monster

Kevin Galbraith as Monster

Maryann Gorka as Monster

Clare Halstead as Monster

Devin Hampton as Monster

Rory Healy as Monster

Drew Lamkins as Monster

Vivian Kyle as Monster

Charlie Leach as Monster

Katie Lumpkin as Monster

Larry Mainland as Monster

Lucky Mangione as Monster

Justin Natic as Monster

Josh Phillips as Monster

Mickie Pollock as Monster

Steve Quinn as Monster

Ashleigh Jo Sizemore as Monster

Jeff Tenney as Monster

Jennifer Trudrung as Monster

Ashton Lee Woolen as Monster

Coleman Youmans as Monster

E. Roger Mitchell as Mayor (uncredited)

Jason Davis as Cyclist (uncredited)

Ella Wahlestedt as Anna (uncredited)

Amber Thrower as Goth Woman (uncredited)