The final appearance by Pippa Haywood as ACC Fenning.
Susannah Corbett makes her first appearance for 5 stories (s4e3 Time To Go).
These are the last appearances by Ellie and Rosie until s9e3, Dead Meat part 1.
The second and final appearance by Tim Barker (as two different characters).
The third and final appearance by Rosie Millar as Rosie Pascoe.