| Name | First Aired | Runtime | Image | |
|---|---|---|---|---|
| S04E01 | Episode 1 |
December 30, 1980
BBC One
|
20 | |
| S04E02 | Episode 2 |
January 2, 1981
BBC One
|
20 | |
| S04E03 | Episode 3 |
January 6, 1981
BBC One
|
20 | |
| S04E04 | Episode 4 |
January 9, 1981
BBC One
|
20 | |
| S04E05 | Episode 5 |
January 13, 1981
BBC One
|
20 | |
| S04E06 | Episode 6 |
January 16, 1981
BBC One
|
20 | |
| S04E07 | Episode 7 |
January 20, 1981
BBC One
|
20 | |
| S04E08 | Episode 8 |
January 23, 1981
BBC One
|
20 | |
| S04E09 | Episode 9 |
January 27, 1981
BBC One
|
20 | |
| S04E10 | Episode 10 |
January 30, 1981
BBC One
|
20 | |
| S04E11 | Episode 11 |
February 3, 1981
BBC One
|
20 | |
| S04E12 | Episode 12 |
February 6, 1981
BBC One
|
20 | |
| S04E13 | Episode 13 |
February 10, 1981
BBC One
|
20 | |
| S04E14 | Episode 14 |
February 13, 1981
BBC One
|
20 | |
| S04E15 | Episode 15 |
February 17, 1981
BBC One
|
20 | |
| S04E16 | Episode 16 |
February 20, 1981
BBC One
|
20 | |
| S04E17 | Episode 17 |
February 24, 1981
BBC One
|
20 | |
| S04E18 | Episode 18 |
February 27, 1981
BBC One
|
20 | |
| S04E19 |
Christmas Special
season finale
|
December 28, 1981
BBC One
|
20 |
No artwork of this type.
No artwork of this type.