Dawn French is back to her funny best in this playfully chaotic and very silly British comedy

Can You Keep a Secret? ★★★½

As grand as it sounds, once you start calling someone a national treasure it tends to limit what they can do. For an artist, it can mean that every project has to be judged as a fitting use of their talents, even if their talent has a simple, welcome basis. Thankfully Dawn French, the British comic who earned the rank of national treasure for the likes of French and Saunders and The Vicar of Dibley, has come back to the sitcom. French has always been funny, and she is funny once more in this drily farcical comedy.

In the BBC’s Can You Keep a Secret?, French plays Debbie Fendon, a retired grandmother in England’s West Country who has the impervious confidence, and perhaps the streak of self-delusion, required to attempt to get things done her way. If that means going against the system, then that’s OK. “Broken Britain,” Debbie will proclaim, happily brushing off convention. The problems start when she stops paying attention to the law.

“Dad was my best friend,” laments Debbie’s only child, Harry (Craig Roberts), who has taken the loss of his father, William, badly. “You should have friends your own age,” replies Debbie, who after two months as a widow isn’t grieving at all. But she takes pity on Harry and lets him on a secret: William (Mark Heap) is alive. A nervy GP and a funeral home mix-up saw him declared dead when he accidentally took too much medication, and once Debbie realised a sizeable life insurance claim was available William was exiled to the attic.

The way this set-up is explained in the first of six episodes is typical of the show’s playful chaos. Repeatedly getting sidetracked, the apologetic William and the unapologetic Debbie take the shocked Harry through the events, the three of them standing to the side of flashbacks as mishap becomes a tainted opportunity. It is ludicrous but tempting – Debbie even has the payout on hand in cash, because she doesn’t trust banks any more.

Created by Simon Mayhew-Archer, whose father Paul was a key writer on The Vicar of Dibley, Can You Keep a Secret? has just enough emotional ballast to make the daftness buoyant. William’s outlook is tempered by his Parkinson’s disease, while Harry, you realise, is a constant mess of neuroses because his parents have long been upending his life. “You and Dad have always done deranged things,” Harry tells Debbie, who seems rather pleased with the observation.

But Harry’s marriage to local police constable Neha (Mandip Gill) is a major complication for someone who, in fact, can’t keep a secret. Then there’s the hooded figure who starts delivering blackmail notes, complete with cut-out lettering, about William’s resurrection and the pay-off they want. The crimes feel like dodgy decisions, poorly conceived and executed with about as much care at the locals put into their mundane daily activities. Even Only Murders in the Building has more genuine risk than this, but the laughs are frequent.

As the plot unfolds, the show hits on a lovely mix of dynamics between separate pairs of characters: father and son, for example, have the shared consolation of living in orbit around Debbie. They should be worried about criminal charges, but William’s main worry is that not being able to go outside has allowed Debbie to cut him off from chocolate runs to the local service station. “I feel like I’m in Requiem for a Dream,” he laments on his second day without treats. Silly? Yes. Enjoyable? Hugely.

Can You Keep a Secret? airs at 8.20pm on Sundays on the ABC, and streams on ABC iview.

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