After a near-fatal illness, Edward Mackay decides to find out more about his late father's mysterious past.

On the sea voyage to the East, the young doctor meets an eclectic crowd including the Simpson sisters, who are of unattainable social class, "both beautiful, one a gazelle".

The doctor is gradually accepted into Penang society, and makes regular visits to the sisters, one of whom is married.

Following a mysterious accident and a secret holiday in the Sumatran highlands, he leaves the island under a cloud of scandal.

Edward's investigations in the modern day are assisted by a trail of clues including a Buddha figurine and a double-one domino, and by an old lady, a blonde woman he bumps into in London, and an Orkney woman called Mica.