• Cast in Order of Appearance: John Hurt (Voice of the Dragon), Katie McGrath (Morgana), Rupert Young (Sir Leon), Adetomiwa Edun (Sir Elyan), Emilia Fox (Morgause), Colin Morgan (Merlin), Zee Asha (Audrey), Eoin Macken (Sir Gwaine), Tom Hopper (Sir Percival), Santiago Cabrera (Sir Lancelot), Bradley James (Arthur), James Greene (Ferryman), Anthony Head (Uther Pendragon), Angel Coulby (Gwen), Richard Wilson (Gaius), Nathaniel Parker (Agravaine), Gemma Jones (The Cailleach), Katie Moore (Drea)
• Written By: Julian Jones
• Directed By: Alice Troughton

• Cast in Order of Appearance: John Hurt (Voice of the Dragon), Colin Morgan (Merlin), Santiago Cabrera (Sir Lancelot), Bradley James (Arthur), Rupert Young (Sir Leon), Adetomiwa Edun (Sir Elyan), Tom Hopper (Sir Percival), Eoin Macken (Sir Gwaine), Sarah Beck Mather (The Vilia), Angel Coulby (Gwen), Richard Wilson (Gaius), Nathaniel Parker (Agravaine), Michael Cronin (Geoffrey of Monmouth), Katie McGrath (Morgana), Anthony Head (Uther Pendragon), James Greene (Ferryman), Gemma Jones (The Cailleach)
• Written By: Julian Jones
• Directed By: Alice Troughton

• Cast in Order of Appearance: John Hurt (Voice of the Dragon), Colin Morgan (Merlin), Bradley James (Arthur), Phil Davis (The Gleeman), Phil Holden (Geldred), Anthony Head (Uther Pendragon), Rupert Young (Sir Leon), Tom Hopper (Sir Percival), Adetomiwa Edun (Sir Elyan), Angel Coulby (Gwen), Nathaniel Parker (Agravaine), Eoin Macken (Sir Gwaine), Richard Wilson (Gaius), Katie McGrath (Morgana), Kyle Lima (Guard), Michael Cronin (Geoffrey of Monmouth)
• Written By: Howard Overman
• Directed By: Alice Troughton

• Cast in Order of Appearance: John Hurt (Voice of the Dragon), James Callis (Borden), Trevoe Sellers (Iseldir), Richard Wilson (Gaius), Colin Morgan (Merlin), Bradley James (Arthur), Nathaniel Parker (Agravaine), Tom Hopper (Sir Percival), Adetomiwa Edun (Sir Elyan), Rupert Young (Sir Leon), Eoin Macken (Sir Gwaine)
• Written By: Julian Jones
• Directed By: Alex Pillai

• Cast in Order of Appearance: John Hurt (Voice of the Dragon), Colin Morgan (Merlin), Steven Hartley (Caerleon), Bradley James (Arthur), Adetomiwa Edun (Sir Elyan), Nathaniel Parker (Agravaine), Tom Hopper (Sir Percival), Rupert Young (Sir Leon), Eoin Macken (Sir Gwaine), Richard Wilson (Gaius), Angel Coulby (Gwen), Lindsay Duncan (Queen Annis), Katie McGrath (Morgana), Kyle Lima (Caerleon's Guard), Robert Maillet (Derian)
• Written By: Jake Michie
• Directed By: Alex Pillai

• Cast in Order of Appearance: John Hurt (Voice of the Dragon), Colin Morgan (Merlin), Bradley James (Arthur), Tom Hopper (Sir Percival), Rupert Young (Sir Leon), Eoin Macken (Sir Gwaine), Adetomiwa Edun (Sir Elyan), Katie McGrath (Morgana), Nathaniel Parker (Agravaine), Richard Wilson (Gaius), Leander Deeny (George), Angel Coulby (Gwen), Zee Asha (Audrey)
• Written By: Lucy Watkins
• Directed By: Alex Pillai

• Cast in Order of Appearance: John Hurt (Voice of the Dragon), Katie McGrath (Morgana), Nathaniel Parker (Agravaine), Colin Morgan (Merlin), Bradley James (Arthur), Duncan Meadows (Orn), Gary Lewis (Alator), Richard Wilson (Gaius), Rupert Young (Sir Leon), Angel Coulby (Gwen), Eoin Macken (Sir Gwaine)
• Written By: Julian Jones
• Directed By: Justin Molotnikov

• Cast in Order of Appearance: John Hurt (Voice of the Dragon), Wayne Foskett (John Howden), Melanie Hill (Mary Howden), Angel Coulby (Gwen), Bradley James (Arthur), Richard Wilson (Gaius), Colin Morgan (Merlin), Rupert Young (Sir Leon), Adetomiwa Edun (Sir Elyan), Eoin Macken (Sir Gwaine), Tom Hopper (Sir Percival), Charlene McKenna (Lamia), Nathaniel Parker (Agravaine)
• Written By: Jake Michie
• Directed By: Justin Molotnikov

• Cast in Order of Appearance: John Hurt (Voice of the Dragon), Nathaniel Parker (Agravaine), Bradley James (Arthur), Colin Morgan (Merlin), Katie McGrath (Morgana), Maureen Carr (The Dochraid), Santiago Cabrera (Lancelot), Angel Coulby (Gwen), Eoin Macken (Sir Gwaine), Adetomiwa Edun (Sir Elyan), Rupert Young (Sir Leon), Tom Hopper (Sir Percival), Richard Wilson (Gaius)
• Written By: Lucy Watkins
• Directed By: Justin Molotnikov

• Cast in Order of Appearance: John Hurt (Voice of the Dragon), Adetomiwa Edun (Sir Elyan), Eoin Macken (Sir Gwaine), Bradley James (Arthur), Rupert Young (Sir Leon), Tom Hopper (Sir Percival), Colin Morgan (Merlin), Nicholas Croucher (Druid Boy), Richard Wilson (Gaius), Nathaniel Parker (Agravaine)
• Written By: Howard Overman
• Directed By: Jeremy Webb

• Cast in Order of Appearance: John Hurt (Voice of the Dragon), Angel Coulby (Gwen), Terence Maynard (Helios), Colin Morgan (Merlin), Bradley James (Arthur), Richard Wilson (Gaius), Nathaniel Parker (Agravaine), Rupert Young (Sir Leon), Adetomiwa Edun (Sir Elyan), Eoin Macken (Sir Gwaine), Tom Hopper (Sir Percival), Tom Meredith (Eoghan), Janet Montgomery (Princess Mithian), Gareth Jewell (Helios' Servant), Katie McGrath (Morgana)
• Written By: Richard McBrien
• Directed By: Jeremy Webb

• Cast in Order of Appearance: John Hurt (Voice of the Dragon), Nathaniel Parker (Agravaine), Bradley James (Arthur), Colin Morgan (Merlin), Richard Wilson (Gaius), Tom Hopper (Sir Percival), Rupert Young (Sir Leon), Adetomiwa Edun (Sir Elyan), Eoin Macken (Sir Gwaine), Katie McGrath (Morgana), Terence Maynard (Helios), Miranda Raison (Isolde), Ben Daniels (Tristan), Caroline Faber (Hunith), Angel Coulby (Gwen)
• Written By: Jake Michie
• Directed By: Alice Troughton

• Cast in Order of Appearance: John Hurt (Voice of the Dragon), Nathaniel Parker (Agravaine), Ben Daniels (Tristan), Colin Morgan (Merlin), Bradley James (Arthur), Miranda Raison (Isolde), Angel Coulby (Gwen), Adetomiwa Edun (Sir Elyan), Eoin Macken (Sir Gwaine), Richard Wilson (Gaius), Katie McGrath (Morgana), Rupert Young (Sir Leon), Tom Hopper (Sir Percival), Terence Maynard (Helios)
• Written By: Julian Jones
• Directed By: Alice Troughton