"What are you doing with your face?" Krissi asked, as I made myself a cheese sandwich in the kitchen. Having been away for two nights, I had a sudden, giddying perspective on just how much margarine seemed permanently smeared on our worktops. This whole room was a health risk. "What do you mean?" I asked--increasing the smugness as I sliced the cheese. "Your face--it's clearly telling me to slap it," Krissi said, staring at me. "It's communicating with me on a frequency you can't hear. It's begging me to slap both cheeks at the same time, like the Three Stooges."