Rhianne Barreto as Sophie (season 1), Hanna’s new friend whose family Hanna meets in Morocco.
Katie Clarkson Hill as Joanne McCoy (season 2), a CIA officer who works under Carmichael at The Meadows.
Cherrelle Skeete as Terri Miller (season 2), a new transfer who is in charge of using social media interaction to cultivate trainees at The Meadows.
Anthony Welsh as Leo Garner (season 2), a supervisor at The Meadows who is responsible for indoctrinating the trainees.
Justin Salinger as Carl Meisner (season 1).
Khalid Abdalla as Jerome Sawyer (season 1).
Ray Liotta as Gordon Evans, a shadowy figure who seems to be the spider at the centre of Ultrax.
Dermot Mulroney as John Carmichael, the CIA operative at the helm of both UTRAX programs.
Roland Kunek, a scientist who designed the regimen for the young agents in the second UTRAX program
Joel Kinnaman as Erik Heller, a former CIA operative who worked for UTRAX but rescued Hanna after falling in love with Johanna, her mother.
Mireille Enos as Marissa Wiegler, the CIA operative put in charge of the original UTRAX program, who has an obsessive interest in Hanna but who turns from a foe to an ally of Hanna.
Esme Creed Miles as Hanna, a girl who was part of the original UTRAX program as an infant but was rescued by Erik Heller, who raised and trained her on his own.