Wendy walked into the foyer carrying a single, nearly weightless grocery bag.

A loaf of bread.

A carton of milk.

The props of her cover story, purchased, I would guess, in the last five minutes of a four-hour absence.

She was wearing a silk blouse I did not recognize, and her hair was styled, and her makeup was fresh and careful — not the appearance of a woman who had spent an afternoon fighting supermarket lines.

And the moment her eyes found me, sitting on the kitchen floor with our son in my arms and our daughter leaning against my shoulder, her whole face flickered, for just a fraction of a second — a flash of pure calculation, of a plan meeting an obstacle it had not accounted for.