Yesterday morning I was in Scarborough. I'd struggled over in the fog for a pre-Christmas visit to my mother and was sitting in the waiting room of one of those places where they fix your car while you wait. I had a flat tyre and a flat battery and that was just the car. I felt pretty flat myself - tail-end of a cold, backache - Xmas shopping still to do, woken up at four by my daughter. But it was OK because I had with me an Agatha Christie I didn't remember reading (my mother is even more of a crime fiction addict than I am - scarcely reads anything else). And it was perfect - undemanding, such a fast, pacey read, and she's funny too. I'd almost finished it by the time the tyre was fitted and I felt better, too. I did pretty much guess who'd done it, but only right at the end. So thanks, Dame Agatha.