You say you are never old in your dreams.

Phllip Marlowe was the quintessential, tough-guy private investigator who fears no one in his bid to track down crooks or locate missing clients. In Only to Sleep, Marlowe is 71 and living below an old Spanish mission a few miles north of Ensenada in Baja. Marlowe remembers the summer of 1950, when he was 30 and at the height of his appeal. At night, his old memories return to a time where the whiskey flowed and the banter was sharp and the sunlight poured over his clients' majestic lawns and driveways. Osborne creates a believable situation in which dangerous riptides do battle against an aging Marlowe.

Marlowe is flattered by the presence of two American insurance adjusters. Knowing that he speaks fluent Spanish, they want him to collect some information, to look into the apparent suicide of an American called Donald Zinn. A real estate developer with a mountain of debt, Zinn has apparently died in a swimming accident at a place called Caeta de Campos. His widow, Dolores, is to be paid two million dollars. But did Zinn commit suicide or die in the course of committing a crime? It's remarkably easy to bribe people and alter facts on a death certificate. Dolores still runs the resort they built together near El Centro, "out in the desert on the American side."

Marlowe shows little regard for the law as he searches for and attempts to expose the truth in a world of drifters and crooks. Tumbling into the Palm Dunes Resort, he meets flirtatious Dolores, "an Able Grable on the make" who tells Marlowe that her marriage was based on two hundred thousand a year and a marina house on Coronado Cays. From the palm trees to the desert's shrill light, Marlowe's presence casts a long shadow of doubt upon Dolores's grief, this "beautiful fraud" who is far more formidable than merely beautiful.

Desperate to stick to the job at hand, Marlowe discovers that Zinn had borrowed ten times more than he could ever pay back while securing a young waitress into a life very different to the one which he had already known. Frustrated at Dolores's smoke-and-mirror explanations, Marlowe returns to his hotel at El Centro. In a ghostly landscape where the dark-red moon hangs above the ragged manzanita trees, instinct moves him as he decides to travel from to Conshas Chinas to Puerto Vallarta, torn between his attraction to Dolores and his increasing pressure to find the whereabouts of Zinn.

This dark, seductive story is fraught with Marlowe's immense tensions and conflicts. His apparent loneliness should not be underestimated. In air edged with the heat and pressure of the desert, Marlowe walks the streets of El Centro, a town lined with bars and restaurants. Like "a sloth in linen with legs long and firm," Marlowe's motions are surprisingly smooth. Suddenly there's the image of Zinn: "the more I observed him the more I became convinced that he was Dolores's husband and that he knew who I was as well."

In the 1980s, Mexico has a seedy, corrupt edge; it's a place where the famous hotel Las Hadas is a magnet for greasy conmen, "the bottom feeders," the little playboys with trim mustaches and "the wealthy Americans with yachts." Dolores is not as cold as she wants to be, though money is something that she understands and greed is something in which she instinctually synthesizes. From the whereabouts of mysterious Paul Linder to Marlowe's jilt and violent near-miss at Las Hadas, Osborne's hero is plunged into a world of nefarious real estate deals as far inland as the Salton Sea. Marlowe is an aging desperado ("being retired isn't so bad."). It's certainly a better life than living in innocuous, run-down hotel rooms and spying on people. Mexico boils and changes before Marlowe's eyes, a patchwork of towns and villages spread across the dry hills. Now there are new bars and restaurants where the affluent white foreigners bring corruption and drugs.

Dolores looks so "magnificently glamourous." Osborne finally strips her down to her essential elements by her fear and by her fate. Though the plot is driven by the mystery of Zinn, the reader's lasting impression is Osborne's dream-like recreation of one of literature's most iconic figures. In Osborne's world, Marlowe finally says goodbye to a lifetime of gorgeous women, broken loves and failed connections.