Cheryl was complaining that she felt light headed. She looked tired, her face slightly swollen, and her posture seemed unusually upright. ‘There’s some sort of bug going round,’ she said. A while later I started to experience similar symptoms. My head felt puffy, and seemed to be pulling me upwards. My whole body in fact had a strange sense of buoyancy as though my feet were about to rise from the carpet. Meanwhile my thoughts were becoming increasingly diffuse. By the time we realised that our heads were swelling up like helium balloons it was too late to try to get help. The crowns of our heads were soon bumping gently against the ceiling, and moving about the room was difficult. Our voices had risen several octaves. I could see my phone lying on the sofa, but there was no way of reaching it.