Dev Patel

Gawain

Alicia Vikander

Lady / Essel

Joel Edgerton

Lord

Sarita Choudhury

Mother

Sean Harris

King

Kate Dickie

Queen

Barry Keoghan

Scavenger

Erin Kellyman

Winifred

Ralph Ineson

Green Knight

Emilie Hetland

First Thief

Anthony Morris

Second Thief

Megan Tiernan

The Young Queen

Helena Browne

Sightless Woman

Brendan Conroy

Taverngoer

Chris McHallem

Lord in Waiting

Atheena Frizzell

Youngest Sister

Donncha Crowley

Bishop

Noelle Brown

Madam

Anaïs Rizzo

Helen

Joe Anderson

Paris

Nita Mishra

Older Sister

Tara Mae

Middle Sister

Sam Uppal Lynch

Prince Age 7

Adam Karim

Prince Age 17

Ruth Patel

Princess Age 4

Rose Patel

Princess Age 6

Emmet O'Brien

Magician

Andrea Deaskovic

Giant

Aoibheann Garry

Giant

Isabel Friosi

Giant

Hannah Sjoden

Giant

Lucy Waters

Giant

Melinda Dempsey

Giant

Rachel Quinn

Giant

Ethan Dillion

Soldier #1 (uncredited)

Aaron Edo

Soldier #2 (uncredited)

Youssef Quinn

Soldier #3 (uncredited)

Patrick Duffy

Gawain's Friend in Tavern (uncredited)

Janet Grene

Townsfolk (uncredited)

Tom Leavey

Knight of the Round Table (uncredited)

Stuart Mackey

Lancer (uncredited)

Aoife Gaffney

Girl at Round Table (uncredited)