Season One
| PRODUCTION NUMBER | EPISODE TITLE | FIRST US TRANSMISSION |
| 6008 | Eleven Days to Zero | 14/9/64 |
| 7204 | The City Beneath the Sea | 21/9/64 |
| 7207 | The Fear-Makers | 28/9/64 |
| 7203 | The Mist of Silence | 5/10/64 |
| 7210 | The Price of Doom | 12/10/64 |
| 7209 | The Sky is Falling | 19/10/64 |
| 7205 | Turn Back the Clock | 26/10/64 |
| 7502 | The Village of Guilt | 19/10/64 |
| 7208 | Hot Line | 9/11/64 |
| 7212 | Submarine Sunk Here | 9/11/64 |
| 7213 | The Magnus Beam | 23/11/64 |
| 7214 | No Way Out | 30/11/64 |
| 7215 | The Blizzard Makers | 7/12/64 |
| 7216 | The Ghost of Moby Dick | 14/12/64 |
| 7211 | Long Live the King | 21/12/64 |
| 7206 | Hail to the Chief | 28/12/64 |
| 7220 | The Last Battle | 4/1/65 |
| 7219 | Mutiny | 11/1/65 |
| 7217 | Doomsday | 18/1/65 |
| 7221 | The Invaders | 25/1/65 |
| 7222 | The Indestructible Man | 1/2/65 |
| 7223 | The Buccaneer | 8/2/65 |
| 7224 | The Human Computer | 15/2/65 |
| 7226 | The Sabateur | 22/2/65 |
| 7227 | Cradle of the Deep | 1/3/65 |
| 7229 | The Amphibians | 8/3/65 |
| 7228 | The Exile | 15/3/65 |
| 7230 | The Creature | 22/3/65 |
| 7231 | The Enemies | 29/3/65 |
| 7232 | The Secret of the Loch | 5/4/65 |
| 7218 | The Condemned | 12/4/65 |
| 7225 | The Traitor | 19/4/65 |