Dylan O'Brien Thomas Ki Hong Lee Minho Kaya Scodelario Teresa Agnes Thomas Brodie-Sangster Newt Dexter Darden Frypan Alexander Flores Winston Jacob Lofland Aris Jones Rosa Salazar Brenda Giancarlo Esposito Jorge Patricia Clarkson Ava Paige Aidan Gillen Janson Lili Taylor Mary Cooper Barry Pepper Vince Nathalie Emmanuel Harriet Alan Tudyk Blondie Jenny Gabrielle Ponytail David House Soldier Lora Martinez-Cunningham Thomas' Mother Shawn Prince David Jeremy Becerra Riley Matthew Page Harold (Soldier) Alex Knight Aide Brandon K. Hampton Surveillance Room Attendant Katherine McNamara Sonya Tatanka Means Joe Ryan Jason Cook Nurse Morse Bicknell Doctor Adriana Acosta Glader (uncredited) Jetto Dorsainville WCKD / Bunker Militia (uncredited) Andrea Good Ash People (uncredited) Carma Harvey Scavenger (uncredited) Keith Jardine Scavenger Guard (Jim) (uncredited) Ben Pronsky Additional Voices (voice) (uncredited) Bryce Romero Jack (uncredited) J. Nathan Simmons Ash Mob Evacuee (uncredited)