A clatter of envelopes shoots through the letterbox, startling her. A pain sears through her head and down the side of her face: the start of a migraine. She picks up the mail addressed to Adam Hawkins and Alison Wood.

Turning left into the living room, she stops dead. French windows overlook a corner garden, so similar to theirs, except this lawn is more like scrubland. The sofa and chairs are the same dark chocolate leather, even the layout of the room is identical. Bright coloured Lego is scattered on a rose-patterned rug, the pattern she chose for their house. She runs a finger along the display cabinet central to the room: dust. Her eyes are drawn to a photo above the mock fireplace. She peers closer, but her eyes blur. It can’t be, but it is. Max is grinning back at her, his arm around the blonde woman, and a boy sitting at their feet. She sways backwards and has to grab onto the sofa to stop herself collapsing. How can this be? This is her husband. It must be a mistake. Are they related? Does Max have a brother, an identical twin? But there, on his upturned wrist, is the unmistakable tattoo of the letter ‘A’.

Stupid, stupid, stupid! She yanks open one of the cabinet doors and a top-heavy pile of board games slides out. The adjacent cupboard is stuffed with colouring books, car magazines, and photo albums. She plucks one out. Bile rises in her throat. Pain pulses through her skull as if her head is about to crack open. She flips open the cover. No, please no. Max’s face is in picture after picture, his unmistakable smile. In one photo, his arm is wrapped around this Alison woman, captured in profile; her small upturned nose close to his cheek, her eyes shut, as if she is inhaling him. On every page Max is with her and the boy, at so many of the same places they’ve visited with the girls: Legoland, London Zoo, The Science Museum. And on holidays where they go: Hunstanton and the Isle of Wight.