Book review: The Hidden Keys by Andre Alexis

The seventh book I read in 2017 was The Hidden Keys by Andre Alexis.  This is a very literary book, in which a heroin-addicted heiress hires a professional thief with a strict code of honor to solve the riddle of her father's will.  He left to each of his five children an unusual item which, when combined with the others, will lead to even greater riches than they have already received.

This book is supposedly "inspired" by Treasure Island, but I couldn't find the parallels.