Mirren in her prime ... one last time LAST NIGHT'S TV

HOW we will miss her. It is 15 years since we were first introduced to Det Supt Jane Tennison (Helen Mirren), then in her prime and fighting her corner in a Met awash with sexist resentment. Last night, in part one of the last ever Prime Suspect, it was a very different Met but the same awkward, troubled Jane.

We found her just weeks from dreaded retirement, waking up on the couch after a big night in with a whisky bottle. She'd been so drunk the night before, she had no memory of the call from her DC to say a 14-year-old girl, Sallie Sturdy, had gone missing.

Cursing herself, she got stuck into the investigation, turning her keen scrutiny on two suspects - Curtis Flynn, a local boy, and Tony Sturdy, Sallie's father. The next day, Sallie's body was found dumped in a muddy puddle on the heath. In the middle of it all, Tennison learned that her own beloved father was dying.

This was vintage Prime Suspect. The tension was palpable right from the start, a sense of the sinister underlying every scene. Tennison's beat is a grey, winter world, an overcast place of rain, bare trees and suspicious faces. The cast - including Scottish actors Gary Lewis and Katy Murphy as Sallie's grief-stricken parents, Stephen Tompkinson as Sallie's headmaster, Philips, and Robert Pugh as DS Simms, a warm-hearted relic of the old order - gave strong support.

But it would count for little without Mirren. As the vulnerable, tenacious Tennison, she was captivating. Her loneliness screamed at us, as she bit back tears in the supermarket, as she clung to her whisky tumbler in her father's empty house and as she sat opposite one-time nemesis Bill Otley (the late Tom Bell) after the death of her father - "I had no-one else to call." Their unexpected rapprochement, after attending the same AA meeting, only served to emphasise Tennison's dislocation from normal life.

Part of the power of Prime Suspect is the fact that, after spending so much time with Tennison, we the audience feel we know her better than most of her own colleagues. Watching her inadvertently exposing her drink problem, or lashing out because one too many people that day had called her a bitch, you could feel her sadness, her panicked sense of isolation, and you wanted someone to reach out to her.

And someone did. As has so often been the case, Tennison discovered a strong affinity with a vulnerable female, this time Sallie's friend and the headmaster's daughter, Penny. After learning Penny wanted to be an artist, Tennison took her to see a Joshua Reynolds painting, the watchful-eyed Strawberry Girl, which she liked as a child. On the way down the steps, Penny slipped her arm into Jane's, a muted but greatly affecting gesture. But you can't help feeling that a happy ending for Jane Tennison is unlikely.

The South Bank Show on Spamalot provided an excuse to show lots of Monty Python clips and did not suffer one bit because of it. How Eric Idle made Holy Grail into an award-winning musical was a good subject and you've got to take your hat off to him for having the energy to pursue it (the other Pythons left him to it). The fact that it was directed by Mike Nichols, Oscar/Emmy/Grammy/Tony-winning polymath, may explain why it worked so well.

What worked less well was an embarrassing sketch in which Idle pretended to be describing the "famously camera-shy" Nichols, who was standing off camera, directing him in what to say. Still, if Idle wasn't prepared to risk things falling flat, he wouldn't have taken a punt on Spamalot - which, as Terry Gilliam suggests, is set to do its bit for the Pythons' pension fund