Sennia Nanua as Melanie

Gemma Arterton as Helen Justineau

Paddy Considine as Sgt. Eddie Parks

Glenn Close as Dr. Caroline Caldwell

Fisayo Akinade as Kieran Gallagher

Anamaria Marinca as Dr. Selkirk

Anthony Welsh as Dillon

Joe Lomas as Joe

Dominique Tipper as Devani

Eli Lane as Kenny

Joel Sheldon as T-Shirt Boy

Will Brooks as Painted Boy

Tessa Morris as Rat Girl

Abigail Sams as Classroom Kid

Shay Gutteridge as Classroom kid

Elizabeth-Anne Fuller as Classroom Kid

Callum Lloyd as Classroom Kid

Alicia Morris as Feral Kid

Matthew Smallwood as Feral Kid

Macey Ward as Feral Kid

Amy Newey as Feral Kid

Elise Reed as Feral Child (Aarra)

Joshua Smallwood as Feral Kid

Stacey Lynn Crowe as Hungry

Amy Floyd as Hungry

Pete Buzzsaw Holland as Hungry 3 (uncredited)

A.k. Steppa as Hungry (uncredited)

Alex Reed as Hungry

Alexandria Wright as Tree Hungry

Ita O'Brien as Pram Lady Hungry

Ria Lopez as Hungry

Sean Evans as Hungry

Ross Green as Hungry

Daniel Jack Evans as Hungry

Samantha Rushton as Hungry

Pamela DeAbreu as Hungry

Rayn Khan as Hero Hungry

Matt Adcock as Hungry

Jim Macie as Hungry

Daniel Eghan as Soldier

Laura Marie Howard as Soldier