[2] Granger joined Gene Hunt's (Philip Glenister) Criminal Investigation Department two years prior to the second series, acting as a uniformed aide with responsibility for administration.

Despite having been referred to as a "lobotomised Essex girl" by Gene Hunt, Granger has demonstrated a "keen intelligence and diverse knowledge" on literature, history and the arts.

However, after she goes on an undercover operation to catch a serial killer - during which she saves herself from an attempt on her life by stabbing her attacker with a screwdriver - and Hunt promises to allow her into CID by Christmas, she decides to stay.

A voice can also be heard; this is later revealed by Chris, who has a similar experience, to be that of Nelson (Tony Marshall), the landlord of The Railway Arms from Life on Mars.

During episode 7 of the first series, Granger attempts to apprehend an armed and dangerous Gil Hollis, shortly after he fired upon the team while they were taking cover in Luigi's trattoria opposite Fenchurch East Police Station.

After Drake's attempts seem to have failed, Hunt orders Hollis to his knees and allows Skelton and Carling to violently assault him while he is in police custody, despite the protest of Viv James (Geff Francis).

They also clash on many political issues, such as Carling's support of Thatcher and his dismissal of opposition to apartheid, leading her to call him "intolerant", "prejudiced", and "racist".

Granger admires DCI Hunt, calling him "brave as a lion", however, in the third season, she becomes frustrated with his harsh treatment of her and her colleagues, especially Chris, and with his inability to keep his promise of promoting her to CID.