Silk, Series Finale, BBC One

Will Silk make it to series two, or will it feel the wrath of BBC One's mad axeman, Danny Cohen? The former, we fervently hope. Despite some implausible incidents and occasionally silly plotlines, Peter Moffat's battling-barristers drama reached the end of its first series looking stronger than when it started.

Much credit for this must go to Maxine Peake's superb portrayal of Martha Costello, the pugnacious girl from the north country pitted against Rupert Penry-Jones's smooth and superior Clive Reader, as both of them strive for that coveted elevation to QC. It was difficult not to feel that Peake identified closely with Costello (though that's what actors worth their salt are supposed to make an audience believe) as she piloted her way through personal crises and the prickly politics of the legal profession, while always striving to cling to the fundamental principles of the law.

Last night's episode six pitched her into the dragon's jaws, as she doggedly defended rent boy Mark Draper (Reece Noi) at his Old Bailey trial for the murder of judge John Guthrie. To make her case stick, Costello had to break down the version of events being sold to the court by Guthrie's widow, Helen (Penny Downie), the embodiment of the grievously wronged, morally impeccable upper-middle-class spouse. Justice Elizabeth Frank (Diana Quick) seemed ill-disposed towards a likely judge murderer, and displayed a distinct inclination to believe the widow's tale.

But as the odds seemed to stack higher against her, Costello's eyes glittered more brightly and her jaw took on a pugnacious jut. Her forensic (literally) dismantling of Mrs Guthrie's evidence was ferocious and unsparing, and blew open a closet full of sordid revelations about the Guthrie family's relationship with Draper. What's more, Costello managed all this despite having to absent herself from the court to suffer a miscarriage. Superwoman indeed.

But Silk couldn't have worked without powerful support from a strong cast. Moffat's writing of the manipulative, devious Clive Reader hasn't quite hit the spot because it hasn't wrung the best out of Penry-Jones and has left him looking underpowered alongside Peake. On the other hand, the interlocking stories of the legal "pupils", Nick Slade and Niamh Cranitch - Tom Hughes and Natalie Dormer (pictured above) - have flourished intriguingly. Beneath Slade's apparent cluelessness and penchant for low-level criminality, an original and audacious mind is starting to reveal itself, while Cranitch is learning that she'll only prosper by carving her own path and leaving aside the fact that her father is a senior judge. And by steering clear of the unscrupulous Reader.

Moffat has also created an unpleasantly realistic atmosphere of backstabbing and career paranoia within Shoe Lane chambers, and has left himself with some mouth-watering set-ups for a putative second series. Much of the dramatic propulsion has come from scheming chief clerk Billy Lamb - a ruggedly gloves-off Neil Stuke (pictured left) - who seems to be resorting to bribery and corruption to bring in more business, and the in-house campaign to get rid of him (led by Nina Sosanya's Kate Brockman) looks set to be bitter and hugely divisive. On top of that, still to be resolved is the recurring saga of the odious thug and stalker Gary Rush (Paul Hilton), who has been lurking in the margins of the show ever since Costello won him an undeserved acquittal in episode one. Perhaps the only major obstacle in Silk's path is the fact that it was commissioned by Jay Hunt when she was controller of BBC One. Cohen's New Broom Syndrome can wreak terrible havoc.

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