It takes courage for an author to create a heroine as intensely dislikable as Christina Cardiff, the protagonist of this dark and wordy thriller.

We first meet Christina at a treatment center in Minnesota where she is trying to cure herself of her drug and alcohol addictions. A wealthy socialite stuck in a loveless marriage with a worthless brute of a husband, Christina is a pathetic creature. Her adulterous relationship with the glamorous, dangerous, and possibly criminal house painter Daniel Cunningham only renders her less sympathetic. When Christina’s husband is found drowned in the swimming pool, Daniel - and by extension Christina - soon become the focus of the police investigation.

To her credit, author Margaret Carroll does not take the obvious route in plotting this book. She could have gone for a neat, easy story of redemption but resists the temptation. Christina loves her son but is unable to care for him; she wants to get clean but repeatedly gives in to the temptation to drink. She engages in loveless, exploitative sex, described in starkly unerotic terms, which only makes her feel even more worthless.

The problem for the reader is that it’s hard to root for such a character. Christina does not seem to be very intelligent or courageous or loving or interested in anyone or anything beyond herself. So why should we care what happens to her?

The other major problem with this book is the writing. Carroll splatters her pages with a blizzard of misplaced metaphors which reach an unfortunate crescendo just as the book approaches its climax.

In that scene, Christina finds herself in the ocean fighting the riptide that gives the book its title. “A thousand sharp stones pelted her feet, scraping her skin raw like knives,” Carroll writes. Then, on the next page: “Her bare skin scraped heavy, cold sand, with stones tearing at her bare body like a million razor blades.” Next page: “Countless shells bit into her skin.”

So which is worse: a thousand sharp stones, a million razor blades or countless shells?

Meanwhile: “Great, swollen towering columns of darkness” are “pushing and pulling her every which way.” And two pages after that: “The ocean, which had been tossing them every which way, suddenly took a ferocious new turn.”

Which way? Every which way.

No wonder that the heroine’s mind was “unfurling itself like a pretzel being pulled apart and laid out straight, end to end for all to see.”

This book has its merits, and the author gets some marks for gutsiness. It could have done with a more sympathetic heroine and a tougher editor.