BBC series "Line of Duty" - holistic vs linear (spoilers)

I just finished Season 1 of Line of Duty (which was brilliant!) and I wanted to share because this series really helped me understand what it means to be a holistic or linear character.

It was especially helpful as this is a gritty ‘male’ show about crime, rather than the usual rom com that I would expect of a holistic story.

The whole world of the series seems to be holistic. It’s about how the police world is corrupt to one degree or another - balancing their duty to uphold the law with their own personal interests.

Gates as MC is balancing his beautiful family life with a secret affair and is continually tested as to whether he will take the honest or the dishonest path. You see him weighing up how bad each thing is and trying to do right by his family, but ultimately is unable to keep the balance.

Arnott as IC is the only linear character. He believes in being a completely straight policeman and even risks his career to tell the truth.

Eventually, the message seems to be that some corruption is inevitable, as MC is steadfast and IC is changed. But it feels like a Failure/Good story because the Arnott’s final lie benefits the Gates’ family.

EDIT Just realised that it’s actually a Failure/Bad story, but because it’s holistic there isn’t a clearcut ending and thus it feels partly positive.