On his first morning of retirement, Edwin Marsh swept the old Hollowbrook post office one last time. Behind a coat rack he found a brass mail slot in a wall that never had one. The little plate read TOMORROW'S DEPARTURES. As a joke, he scribbled a grocery list and fed it in. By noon, the milk he'd written down sat on his porch, in a glass bottle stamped with tomorrow's date.

Edwin decided the slot was a trick, maybe a prank from the new postmaster. He marched next door to ask his neighbor Rosa if she'd seen anyone sneaking around his porch that morning.