First of all you've got the flashing lights casting dramatic colour into everyone's faces, grim expressions steeped alternately in criminal red and smoky blue. Then there's the sound of the sirens on the night, like an elevator ratcheting down the levels of the city, the crackling voices of the comsets, somehow brisk and mysterious at the same time, the coming and going of dimly lit bulky figures and snatches of cryptic conversation, the deployed technology of law enforcement for wakened bystanders to gape at, the lack of anything else going on to provide a vacuum backdrop. There can be absolutely nothing to see beyond this and people will still watch for hours.