The windswept Devon island adored by Agatha Christie

Burgh Island certainly knows how to make an entrance. As you descend the hill at dusk into Bigbury-on-Sea the white hotel drinks up all the light. Like a flashy piece of costume jewellery, it’s the only thing you notice on the skyline. But, then again, it's used to making good first impressions. Despite its diminutive size, the island appears in Agatha Christie's Evil Under the Sun before any of the novel’s characters, upstaging even Hercule Poirot.

The reader is never in any doubt that the book's murder will hinge entirely on ‘the little windswept gull-haunted promontory – cut off from land at each high tide’ and the ‘comfortable and most exclusive hotel’ on its most northerly shore.

Christie isn’t known for her sense of place: her settings are usually seen as blank canvases for the crimes, dashed off in a few sentences before the plot can get underway. But it would be wrong to assume she didn’t care about setting – and nowhere is this more true than South Devon's Burgh island, a landscape she knew intimately.

Christie came to Burgh for its heady mix of isolation and glamour: the Art Deco hotel that first opened on the island in 1929 quickly found itself a society favourite. It welcomed everyone from Prince Edward and Wallis Simpson to Winston Churchill in its heyday. Christie – already a household name by the time she visited – had a beach house there, to which she would frequently retreat in order to write And Then There Were None and  Evil Under the Sun. The beach house has of course been lovingly restored by the hotel and guests can now stay in it (for a price).

Beyond the glitz, the island appealed to Christie as a literary setting. Her books are full of enclosed spaces: trains, ships, islands. And Burgh island’s neat circumference offered her a concise geography in which characters can only be present in a small number of places within a set period of time. Yet the best plots demand a small measure of chaos; at low tide, the secluded Burgh island suddenly becomes open to anyone who strolls across the causeway from the mainland. Will the murderer be a guest from the hotel or a stranger from afar? I imagine Christie loved Burgh because it was both finite and infinite; entirely known and yet rendered unfamiliar at each new tide.

Little wonder, then, that Christie fans flock to the restored Art Deco hotel in their droves. This is not a place where things are done by halves: cocktails on arrival, corded rotary phones in the rooms and black tie for dinner in the ballroom where guests go to town with sequins and flapper dresses. Everything teeters on the edge of pastiche and yet, cut off as you by the sea, you can’t help but indulge.

After all, Christie was known to have harboured a few indulgences of her own; she purportedly kept a cup of cream by her typewriter and, according to her grandson, used to eat clotted cream neat from the pot with a spoon. Indeed, Burgh island has its very own Agatha inspired cocktail – Hibernation – which mixes Baileys, Kahlua, Amaretto and cream. In the novels, a taste for cream is a mark of good character. Miss Marple was, of course, a lover of cream and even Poirot was partial to it.

Burgh certainly gives you the feeling that you can get away with these sorts of eccentricities. On our second night in the hotel we watched an elegant older bride – with a figure that would reduce even Helen Mirren to envy – arrive in a 1920s gown, her newly wedded husband in a red velvet dinner jacket. The unapologetic nostalgia of this place will cause London types to squirm but for the rest of us the make believe is nothing short of a delight. Even the staff seem in on the act. Their opening gambit of ‘What brings you to Burgh?’ almost invites you to invent an elaborate alibi. It's as though, by crossing the causeway, you've arrived in another world – one where the usual rules don't apply.

Period features do at times take precedence over practicality; but, then again, pragmatists are less wont to maroon themselves on windswept islands for the weekend. It certainly didn’t come as a surprise to me that the accomplice in Evil Under the Sun is given away by gurgling bath water. Authenticity is the name of the game here – including deliciously old-fashioned baths and plumbing to match.

Readers of Evil Under the Sun will relish a trip to Mermaid Pool – the enclosed bathing spot where Hercule Poirot first sets eyes on the glamorous Arlena. The tidal pool where Christie’s murder victim makes her memorable entrance was painstakingly restored with the help of the army in the 80s, complete with a round bathing table in the middle where guests can sit and sun themselves – an island within an island. Protected by rocks on all four sides, we wiled away an entire afternoon here on the deck chairs in late November with no thought as to what might be happening on the mainland.

Every true Agatha aficionado will set off on the well trammelled route across the island to the inlet she dubs ‘Pixie Cove’– the site of the murder in Evil Under the Sun. The ever-economical Christie leaves it to the reader to conjure up the stark drama of Burgh’s cliffs. The sheer drop is only really inferred in the novel through Patricia Redfurn’s apparent vertigo when faced with the climb down to the cove, which later helps Poirot solve his case. And so Burgh's visitors have the joyous task of scurrying around the tall cliffs and turquoise inlets to fill in the aesthetic details that Christie left to the imagination.

Christie’s novels are like clocks; every sentence has purpose and the beauty is in the utility. The opposite could be said of Burgh Island which, having long lost any practical use (it used to house a monastery), now exists purely for pleasure. But, as Christie herself once famously said: 'just to be alive is a grand thing' and this is place that leaves you feeling marvellously full of life.

At high tide, guests come and go via sea tractor – a giant wheeled contraption built in 1969 by the man who masterminded Britain's nuclear programme. Trundling off into the waves with your luggage on this rusty behemoth feels like an act of madness. But, as with everything on Burgh, common sense is best left at the door (or on the mainland, to be precise).