I have been spending the last few weeks at The Denizen, a luxury apartment block built by Taylor Wimpey in Golden Lane, just inside the border between the City of London and Islington. I got an email about a month ago from a Mr. Jason Chan, who it seemed had bought an investment property in the building, and on staying in it for a few days while holidaying in London, found that he had purchased a very peculiar piece of real estate. His flat in The Denizen has got a most infernal whistling in it, sort of haunting it. The thing starts any time, you never know when, and it goes on until it frightens you. It's not ordinary whistling and it isn't the wind. Wait till you hear it.