“Do you know, I never realised how utterly dreadful television is without chocolate,” says Mark Heap’s William Fendon as he settles down for a night’s viewing without a treat to hand. And there may be moments in the slightly iffy early stages of Can You Keep a Secret? (BBC1) when even those on a January diet will feel inclined to reach for the Choco Leibniz.

The writer Simon Mayhew-Archer’s premise is that semi-reclusive William had a funny turn when he overdid his Parkinson’s medication and is declared dead by the doctor. An even more unlikely-seeming clerical error at the local Somerset undertakers prompts his wife, Debbie (Dawn French, who has played Heap’s wife before, in ITV1’s The Trouble with Maggie Cole), to carry on with the ruse so that they can claim a whopping insurance payout. Matters are further complicated when the couple’s son, Harry (Craig Roberts) — a gentle, doe-eyed foil to his eccentric parents — finds out. His wife, Neha (Mandip Gill), is a copper whose career would be over if she gets involved.

Not that it really matters, but this isn’t actually that far-fetched. Remember John Darwin, the “Canoe Man”? You could think of this as a comic retelling. Mayhew-Archer astutely leans into the weirdness and things get motoring when the couple are forced to deal with an anonymous blackmailer who has discovered the ruse. The jeopardy is rocket fuel for a series that, like Daisy May Cooper’s brilliant Am I Being Unreasonable?, suggests a promising trend in British comedy for well-plotted shows with a meaningful narrative arc that cleverly dispenses with the obligation for a classic sitcom “reset” every episode.

Some of the gag-making could be a bit sharper and there is a running joke about a local eccentric called Pigfish who keeps putting a petrol pump up his rear end that is probably not as funny as the production team clearly think it is. The same can be said for Debbie’s constant refrains about “broken Britain”. But it’s beautifully performed, with the always brilliant Heap showcasing his comic timing, physical skills and capacity to wring depth as well as hilarity from every line. I loved his marital advice to his son: “Just do what generations of brave Fendons have done before you: grovel.”

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Whatever one thinks of French’s social media pronouncements on international affairs, her talent is undeniable and here she is excellent at showcasing the flecks of selfishness beneath Debbie’s blowsy bluster. She’s a much darker performer than she’s usually given credit for and there are moments when she is truly horrible to both the men in her life as well as her two friends, one a blind woman, the other a narcoleptic. I also liked the show’s defiantly unaspirational vibe; the Fendon homestead is so fantastically messy you can almost smell it. So British.

There is real heart here. Mayhew-Archer’s dad, the Vicar of Dibley co-writer Paul, has Parkinson’s disease and his son’s work with the woman who played the Rev Geraldine Granger delivers a poignancy that isn’t always in evidence in the scene-setting first 30 minutes.

So stick with this. It’s a surprising treat, sweet and butter-soft in places but with just the right note of astringency to delight even the fussiest chocophile.
★★★★☆
All episodes are available on iPlayer

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