You know already that David Renwick is not afraid of killing off beloved characters. He created everyone’s favourite po-faced OAP Victor Meldrew, and when the time came he was good enough to grant him a quick death. Sad, but quick.

Shame there’s no such luck for Jonathan Creek, who has been left to a slow lingering demise, executed in the form of the cruellest punishment: murder by disapproving audience.

This was the series that would either be the death row reprieve or the last meal for Jonathan Creek. When you ask people what the last good episode was before Series 5 they all assume the same expression; their eyes roll brainwards and their mouth contorts. ‘That one with the speedboat…?’ they might venture, and only then because they caught a repeat on UKTV Drama the other night.

At the outset, ‘Curse of the Bronze Lamp’ had all the makings of one of those mouth-contorting episodes. A locked-room mystery you could get your teeth into; a great appearance by yesteryear’s funnywoman Josie Lawrence; Jonathan being oblivious to a woman’s emotional needs… it almost felt like it was 1998 all over again. The Beeb should have aired an episode of Bugs beforehand, and given everyone a plate of cheesy beans on toast, just to really set the scene.

I’ve said before, Creek is a show sustained by rose-tinted nostalgia. It’s no surprise that it nudges toward improvement when it embraces that. Yet this was, at best, an echo of the show’s heydays. The shadow of the audience’s Platonic ideal of the magic mop-head. Of course we relax our disbelief when sitting down to watch Jonathan Creek – the show wears improbability like a duffel coat – but this was an hour in which disbelief, credulity, and solutions were stretched thinner than a balloon skin in order to make captured Lindsay Isherwood look like the Houdini of hypothetical escape ploys.

If this is the final Creek, then it’s both a reason why the audience will miss the show and why it should end. It had the confidence and energy of a Series 2 instalment at the outset, but none of the style or logic to shore that up later.

What was meant to be an ingenious SOS looked like a loose knotting of far-fetched coincidences: a watch, dangling unnoticed in Josie Lawrence’s hair; the normally uptight Polly helping move a dead body rather than calling the police; the wind being an accomplice in solving a crime. Put together it was all so…flimsy.

Or perhaps you didn’t notice because you were pondering why there were two June Whitfields, and even the answer then was disappointing. A lot of trickery for no purpose. But trickery without purpose has been the motif of Jonathan Creek‘s fifth series, hasn’t it?

Of course, Jonathan Creek may still pull off the ultimate illusion and return. But really, after this series, the best thing would be to Meldrew him. Kill him off. And ideally do it in a locked room, just to give us something to actually engage with.

Aired at 9pm on Friday 14 March 2014 on BBC One.

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