A bookshop is a building full of strangers' lives.

You never met Arthur Pell. The solicitor's letter named you — Iris Calloway, of an address he had no reason to know — the will was in order, and the keys work. Above the door, in flaking gold: HERITAGE & SONS, and nobody left alive remembers any sons. Inside: his coat on the hook, his lamp on the counter, a ledger that stops mid-word — and shelving rules too strange to be housekeeping. The Baedeker is never shelved beside the atlases.

Every book here carries its previous owner.

Pressed violets from a garden that flowered at night. Love letters conducted entirely in the margins of second-hand novels. A soldier's promise folded into a book that outlived both parties. Buy and sell them, find the book each customer is really asking for, and keep the shop alive through the autumn of 1994.

And in the margins, one hand keeps recurring.

The inks age. The handwriting never does. It signs itself only "M." Pell spent years tracking it through his stock; his files are still in the back room, exactly where he left them, and the last thing he wrote was addressed to you: shelve by the rules, and do not read the margins.

How much you read is up to you. It always was.

What's inside

• Keep the shop — buy collections, price finds, match books to the people who need them.
  
• Read the owners — marginalia, inscriptions, photographs and pressed things, drawn from five decades of previous owners.
  
• Follow the files — the previous owner's investigation, exactly where he left it.
  
• Choose what the collection becomes — what you keep, what you release, and how close you let the hand in the margins come. Four endings.
  
• Painted London, 1994; rain on the glass, lamplight in the aisles — and the back rows, where the bulbs keep dying.