| Name | First Aired | Runtime | Image | |
|---|---|---|---|---|
| S04E01 | Episode 1 |
January 23, 2017
National Geographic (UK)
|
22 | |
| S04E02 | Episode 2 |
January 30, 2017
National Geographic (UK)
|
22 | |
| S04E03 | Episode 3 |
January 30, 2017
National Geographic (UK)
|
22 | |
| S04E04 | Episode 4 |
February 20, 2017
National Geographic (UK)
|
22 | |
| S04E05 | Episode 5 |
February 17, 2017
National Geographic
|
22 | |
| S04E06 | Episode 6 |
February 6, 2017
National Geographic (UK)
|
22 | |
| S04E07 | Episode 7 |
February 13, 2017
National Geographic (UK)
|
22 | |
| S04E08 | Episode 8 |
February 20, 2017
National Geographic (UK)
|
22 | |
| S04E09 | Episode 9 |
February 20, 2017
National Geographic (UK)
|
22 | |
| S04E10 | Episode 10 |
January 30, 2017
National Geographic (UK)
|
22 | |
| S04E11 | Episode 11 |
February 27, 2017
|
22 | |
| S04E12 | Episode 12 |
February 27, 2017
National Geographic (UK)
|
22 | |
| S04E13 | Episode 13 |
January 30, 2017
National Geographic (UK)
|
22 | |
| S04E14 |
Episode 14
season finale
|
February 27, 2017
National Geographic (UK)
|
22 |
No artwork of this type.
No artwork of this type.
No artwork of this type.