Prime Suspect 6: The Last Witness

Jane Tennyson is 54. She's a Superintendent in charge of 20 murder investigations. As, usual, she is fighting sexist discrimination within the force and now ageism. The detective (Mark Strong), who used to work on her team, is her boss.

Things have changed since we saw her last, six years ago. For one thing, she's looking better than ever and has learnt how to play the political game like a pro. She won't accept rulebook commitment. She demands more and, as a result, does not lack detractors amongst the younger staff.

She makes assumptions - what used to be called gut instinct - and is not always right. Despite a tough exterior, she allows emotion to cloud the issue. Behind the uniform (which she doesn't wear) and the job description, she is a woman who uses charm and manipulation as weapons in her armory.

"It would be a sincere miscalculation to undermine my authority," she says, and you believe her.

A girl, possibly an illegal, possibly a Bosnian, possibly on the game, has been tortured and murdered. Tennyson takes this one seriously and, through intense investigation, finds that it leads to a barely known massacre of Muslims during the civil war.

She is up against a ruthless, faceless enemy, with only sketchy intelligence, a photojournalist ex-boyfriend (Liam Cunningham) and her doggedly irreverent team of detectives to aid and abet. The dead girl's sister (Ingeborga Dapkunaite), who works as a cleaner in a hospital, understands the power that the torturers have. "That's why they rape you," she tells Tennyson. "Because you are always ashamed."

The script by Peter Berry is sharp, tight, witty and intelligent, matched by supremely confidant actors, working in the Prime Suspect style of disciplined individuality. Helen Mirren has made Jane Tennyson her own, but this time is even more impressive. Not only does she live and breathe the contradictions of this ambitious, determined woman, exposing her defects as honestly as her strengths, but makes you feel her passion for justice in a world degraded by cynicism and corruption.

Why is it that thrillers of this quality can be made for television, but not for the cinema? The question remains hanging like a Florida chad.