| One season – 32 episodes | ||
| 29. 9.67 | The Mysterons | 1 |
| 6.10.67 | Winged Assassin | 2 |
| 13.10.67 | Big Ben Strikes Again | 3 |
| 20.10.67 | Manhunt | 4 |
| 27.10.67 | Avalanche | 11 |
| 3.11.67 | White as Snow | 8 |
| 10.11.67 | The Trap | 13 |
| 17.11.67 | Operation Time | 6 |
| 24.11.67 | Spectrum Strikes Back | 10 |
| 1.12.67 | Special Assignment | 14 |
| 8.12.67 | The Heart of New York | 16 |
| 15.12.67 | Lunarville 7 | 15 |
| 22.12.67 | Point 783 | 5 |
| 29.12.67 | Model Spy | 18 |
| 5. 1.68 | Seek and Destroy | 9 |
| 19. 1.68 | Renegade Rocket | 7 |
| 26. 1.68 | Crater 101 | 21 |
| 2. 2.68 | The Shadow of Fear | 12 |
| 9. 2.68 | Dangerous Rendezvous | 22 |
| 16. 2.68 | Fire at Rig 15 | 19 |
| 23. 2.68 | Treble Cross | 24 |
| 1. 3.68 | Flight 104 | 26 |
| 8. 3.68 | Place of Angels | 27 |
| 12. 3.68 | Noose of Ice | 23 |
| 26. 3.68 | Expo 2068 | 28 |
| 2. 4.68 | The Launching | 29 |
| 9. 4.68 | Codename Europa | 30 |
| 16. 4.68 | Inferno | 25 |
| 23. 4.68 | The Traitor | 17 |
| 30. 4.68 | Flight to Atlantica | 20 |
| 7. 5.68 | Attack on Cloudbase | 31 |
| 14. 5.68 | The Inquisition | 32 |
As re-screenings have shown, the series featured a variety of opening and closing titles:
Captain Blue narration, probably the version heard on most other episodes:
The Mysterons – sworn enemies of Earth, possessing the ability to recreate an exact likeness of an object or person; but first they must destroy.
Leading the fight, one man fate has made indestructible.
His name – Captain Scarlet
Captain Blue narration, a rare version, possibly on American prints[?]:
One man, a man who is different. Chosen by fate, caught up in Earth's unwanted conflict with the Mysterons. Determined, courageous, indestructible.
His name – Captain Scarlet.
This is then followed by Colonel White's 'warning':
Captain Scarlet is indestructible. You are not. Remember this; do not try to imitate him.
| One season – 30 episodes | ||
| 29. 9.68 | Most Special Agent | 1 |
| 6.10.68 | Most Special Astronaut | 11 |
| 13.10.68 | Project 90 | 16 |
| 20.10.68 | Hi-Jacked | 2 |
| 27.10.68 | Colonel McClaine | 17 |
| 3.11.68 | The Fortress | 15 |
| 10.11.68 | King for a Day | 9 |
| 17.11.68 | International Concerto | 4 |
| 24.11.68 | Splashdown | 3 |
| 1.12.68 | Big Fish | 6 |
| 8.12.68 | Relative Danger | 7 |
| 15.12.68 | Operation McClaine | 5 |
| 22.12.68 | The Unorthodox Shepherd | 8 |
| 29.12.68 | Business Holiday | 10 |
| 5. 1.69 | Arctic Adventure | 14 |
| 12. 1.69 | Double Agent | 13 |
| 19. 1.69 | Three's a Crowd | 12 |
| 26. 1.69 | The Professional | 20 |
| 2. 2.69 | The Race | 19 |
| 9. 2.69 | Talkdown | 21 |
| 16. 2.69 | Breakout | 22 |
| 23. 2.69 | Child of the Sun God | 23 |
| 2. 3.69 | See You Down There | 29 |
| 9. 3.69 | Lone Handed 90 | 18 |
| 16. 3.69 | Attack of the Tiger | 26 |
| 23. 3.69 | Viva Cordova | 25 |
| 30. 3.69 | Mission X-41 | 27 |
| 6. 4.69 | Test Flight | 28 |
| 13. 4.69 | Trial at Sea | 24 |
| 20. 4.69 | The Birthday | 30 |
| One season – 13 episodes | ||
| 21. 9.69 | A Case for the Bishop | 1 |
| 28. 9.69 | A Question of Miracles | 2 |
| 5.10.69 | To Catch a Spy | 3 |
| 12.10.69 | The Feathered Spies | 4 |
| 19.10.69 | The Last Train to Buffler's Halt | 5 |
| 26.10.69 | Hole in One | 8 |
| 2.11.69 | Recall to Service | 7 |
| 9.11.69 | Errand of Mercy | 6 |
| 16.11.69 | The Deadly Whisper | 11 |
| 23.12.69 | The Cure | 10 |
| 30.11.69 | School for Spies | 9 |
| 7.12.69 | May-day, May-day! | 12 |
| 14.12.69 | More Haste – Less Speed | 13 |