As London is submerged below floodwaters, a woman gives birth to her first child. Days later, she and her baby are forced to leave their home in search of safety. They head north through a newly dangerous country seeking refuge from place to place.

Sally Lockhart has struck a man dead with just three words, sent to her in a message from her father just before he drowned in the South China Seas. But unfortunately, Sally has no idea what the words The Seven Blessings mean. Before long, she is drawn into a mystery filled with opium, secrets from her own past and, at the heart of it all, the Ruby of Agrapur.

A successful writer of children's books, Stephen Lewis is confronted with the unthinkable—he loses his only child, four-year-old Kate, in a supermarket. In one horrifying moment that replays itself over the years that follow, Stephen realises his daughter is gone. Kate's absence sets Stephen and his wife on diverging paths as both struggle with an all-consuming grief.