Alas! As quickly as Silent Witness came back it’s now time for the series to disappear again until next year’s momentous anniversary.

It’s fair to say that the nineteenth season of BBC One’s long-running crime drama has seen the show reach new heights, with this week’s two-part finale ensuring it still remains must-see television after two decades.

Penned by frequent series writer, Ed Whitmore, ‘River’s Edge’ tells a complex story of debauchery and murder. In the opening episode, the Lyell team arrive at the scene of a shooting where Kate Blair and her partner, Chris Chandler are found dead inside a car beside the River Malt. Kate’s son, Dan is found alive but severely injured.

At first the signs point to a simple case of family annihilation and as the evidence mounts up against ex-husband Miles Blair, DCI Sally Butcher is convinced she’s got her man. Yet further unravelling of the evidence reveals a much more sinister plot and a connection to the suspicious death of Karen Myers in the same location ten years before.

Elsewhere, Amy Coulter is summoned to Simon Forsyth’s house where her skills as a doctor are called upon to treat a significant chest wound on Erich Schrader, a man she recognises from her past.

DS Malcolm Guillam enlists the assistance of Jack and Nikki as they search the surrounding area for the fourth victim. There’s a dire twist, however, when Guillam inadvertently stumbles upon two missing bodies at Bellmead Farm and is swiftly shot dead. Back in the woods, Nikki and Jack realise they’ve made a fundamental error in the case. ‘We’ve been looking down the wrong end of the telescope,’ proclaims Nikki as the reality becomes clear.

As the story unfolds in part two we discover the bodies in the freezer at Bellmead Farm are Bella and Natalie Day, and there’s evidence of sexual assault and drugging before their deaths.

With the spotlight cast on her, Claudia Baxter confronts Forsyth and threatens to own up to her involvement in the killings. ‘We’ve all got our hands dirty one way or another. We’re all implicated,’ she tells Forsyth whose mask of indifference slips slightly. Under Butcher’s questioning, Claudia is told her parties led to the deaths and she’s therefore complicit.

Believing her to hold vital knowledge, Nikki pesters Amy to come forward and assist with the case, however, at first she’s too scared but eventually reveals the identity of Schrader, and his connection to Karen’s murder in 2005. Examining Schrader’s injury, Nikki notes that ‘it looks more like a stab wound.’ Unfortunately no fingerprints are found and Butcher is forced to release him.

After looking through Karen’s case-file, Amy heads to Forsyth’s house to question Schrader about her, telling him that his was the ‘last face she ever saw.’ With her usual uncanny ability to walk straight into mortal danger, Nikki tries to help Amy who sports fresh injuries but Forsyth attacks her as his grip on the situation finally unravels. Fortunately, Amy overpowers him and Nikki’s life is saved. Phew.

Having been explicitly linked to the killings, Forsyth is arrested but Schrader is already preparing to board his flight, and Claudia is charged with conspiracy to pervert the course of justice. As a shaken Nikki heads back, Thomas calls to check on her.

Bolstered by an impressive guest cast including Nick Sidi, Derek Griffiths, Sally Carman and Clare Holman, ‘River’s Edge’ is an intelligent and sometimes dark story complimented by an impressive score from Sheridan Tongue that sends the show out in style.

It’s been tremendous, Silent Witness, and I can’t wait for Season 20.

Aired at 9pm on Monday 1 February 2016 and at 9pm on Tuesday 2 February 2016 on BBC One.

> Buy Season 18 on DVD on Amazon.

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