Book 71: "The Ruby in the Smoke" by Philip Pullman

[kittiwake]

... a place of darkness, under a knotted rope. Three red spots shine on the spot when the moon pulls on the water. Take it. It is clearly yours by my gift, and the laws of England. Antequam haec legis, mortuus ero; utinam ex animo hominum tam celeriter memoria mea discedat.

Sally Lockhart's father has died leaving a mystery behind him, a mystery concerning a stolen ruby shrouded in the smoke of an opium den. An exciting tale of VIctorian England and the Far East.