A secret, high-technology international agency called SHADO defends Earth from alien invaders.
| Title | Air Date | Duration | ||
|---|---|---|---|---|
| Season 1 | Episode 1 | Identified | 1970-09-16 | 60 min |
| Season 1 | Episode 2 | Exposed | 1970-09-23 | 60 min |
| Season 1 | Episode 3 | The Cat with Ten Lives | 1970-09-30 | 60 min |
| Season 1 | Episode 4 | Conflict | 1970-10-07 | 60 min |
| Season 1 | Episode 5 | A Question of Priorities | 1970-10-14 | 60 min |
| Season 1 | Episode 6 | E.S.P. | 1970-10-21 | 60 min |
| Season 1 | Episode 7 | Kill Straker! | 1970-11-04 | 60 min |
| Season 1 | Episode 8 | Sub-Smash | 1970-11-11 | 60 min |
| Season 1 | Episode 9 | Destruction | 1970-12-02 | 60 min |
| Season 1 | Episode 10 | The Square Triangle | 1970-12-09 | 60 min |
| Season 1 | Episode 11 | Close Up | 1970-12-16 | 60 min |
| Season 1 | Episode 12 | The Psychobombs | 1970-12-30 | 60 min |
| Season 1 | Episode 13 | Survival | 1971-01-06 | 60 min |
| Season 1 | Episode 14 | Mindbender | 1971-01-13 | 60 min |
| Season 1 | Episode 15 | Flight Path | 1971-01-20 | 60 min |
| Season 1 | Episode 16 | The Man Who Came Back | 1971-02-03 | 60 min |
| Season 1 | Episode 17 | The Dalotek Affair | 1971-02-10 | 60 min |
| Season 1 | Episode 18 | Timelash | 1971-02-17 | 60 min |
| Season 1 | Episode 19 | Ordeal | 1971-04-14 | 60 min |
| Season 1 | Episode 20 | Court Martial | 1971-05-01 | 60 min |
| Season 1 | Episode 21 | Computer Affair | 1971-05-15 | 60 min |
| Season 1 | Episode 22 | Confetti Check A-O.K. | 1971-07-10 | 60 min |
| Season 1 | Episode 23 | The Sound of Silence | 1971-07-17 | 60 min |
| Season 1 | Episode 24 | Reflections in the Water | 1971-07-24 | 60 min |
| Season 1 | Episode 25 | The Responsibility Seat | 1973-03-08 | 60 min |
| Season 1 | Episode 26 | The Long Sleep | 1973-03-15 | 60 min |
