| Name | First Aired | Runtime | Image | |
|---|---|---|---|---|
| S04E01 | Episode 1 |
November 17, 2018
BBC One
|
60 | |
| S04E02 | Episode 2 |
November 24, 2018
BBC One
|
60 | |
| S04E03 | Episode 3 |
December 1, 2018
BBC One
|
60 | |
| S04E04 | Episode 4 |
December 8, 2018
BBC One
|
60 | |
| S04E05 | Episode 5 |
December 15, 2018
BBC One
|
60 | |
| S04E06 | Christmas Special |
December 25, 2018
BBC One
|
60 | |
| S04E07 | Episode 7 |
January 5, 2019
BBC One
|
60 | |
| S04E08 |
Episode 8
season finale
|
January 12, 2019
BBC One
|
60 |
No artwork of this type.
No artwork of this type.
No artwork of this type.