"We want people here to enter into the spirit of the thing and to have fun" - but this does not, Clark stresses, mean Agatha Christie Murder Mystery weekends. "It's just a matter of doing something that makes you feel glamorous. You can actually wear a DJ here and not feel like an idiot." Inevitably, Clark and Orchard want to attract people who like the creature comforts of Islington but won't panic when the tide comes in. "It's an adventure coming here, a more exacting experience than the country house hotel, where you know what to expect. You have to accept being cut off twice a day, but it does give you your own private kingdom." The famous sea tractor which transports guests across the water can't operate when the weather conditions are too stormy, which adds a frisson of uncertainty to out-of-season visits.