Ros' introduction to the team

[Alpha One]

I always wondered whether Ros was based on the Angela character from S4.10. A brilliant female spook: totally uncompromising and ultimately flawed.

Her introduction demonstrated how far she was prepared to go but also that she had boundaries. Although she brought her father down eventually, he remained her Achilles heel as we also saw in ep4 and 5 of S5 and when she was recruited by Yalta.