[11] In summer 1917, a Chinese laborer is accused of stealing from the company stores of the Spokane International Railway in the Idaho Panhandle.

Grainier stops in Meadow Creek and buys a bottle of sarsaparilla for his wife, Gladys, and their four-month-old daughter, Kate.

He meets fellow worker Arn Peeples, a fearless but superstitious old man who dangerously excavates tunnels with dynamite.

In summer 1920, Grainier returns to Idaho from working on the Robinson Gorge to find a massive wildfire has consumed the valley.

Four years into living in his cabin, Grainier realizes he cannot continue to move out every summer to Washington and every winter to Bonners Ferry.

Grainier is visited by a figure of his wife Gladys, who tells him she died after falling and breaking her back on rocks down by the river.

Thereafter, Grainier lives in his cabin, working one final summer in the Washington woods to pay for winter lodging for his horses.

[13] Publishers Weekly called the novella "the synthesis of Johnson's epic sensibilities rendered in miniature in the clipped tone of Jesus' Son.

"[15] K. Reed Petty, for Electric Literature, said "Train Dreams, luscious with grief, regret, and lowered expectations, is a lesson in end-of-the-frontier humility for a country anticipating apocalypse.

"[16] In Ploughshares, Jocelyn Lieu said that the novel was "a brilliantly imagined elegy to the lost wilderness of the early 20th-century Idaho Panhandle".

[17] James Wood in The New Yorker rated Train Dreams "a severely lovely tale" and Eileen Battersby of The Irish Times declares that "Johnson's novella, Train Dreams, a daring lament to the American West, is a masterpiece which should have won him the Pulitzer Prize but was short-listed in a year that the jury decided not to award it.

[20][21] Literary critic Anthony Wallace praises Johnson's sustained and skillful use of this stylistic device: "Johnson is indeed a very good Hemingway disciple, perhaps even a great one…the true, simple declarative sentence is alive and well here..."[22] Wallace points out that Johnson's use of "free indirect discourse" serves to convey the simple and unaffected quality of his protagonist: "[M]ost of what we know about Grainier on the inside is achieved indirectly, suggestively" in the manner of Hemingway.

[23] Critic James Wood praises Johnson's Hemingwayesque writing: "Johnson often uses an unobtrusive, free indirect style to inhabit the limited horizons of his characters",[24] adding this caveat: There is a kind of pure, clean American simplicity in prose that is easy to mimic and hard to make.

Sometimes, after the beautiful monotonies of Hemingway, one longs to bathe in impurities—to take on the luxuries and rough excesses of a more abundant style.

[26] Literary critic Alan Warner sums up Grainier's fate as follows: The denouement of Train Dreams is so tragic and surreal that the reader at first denies its grisly approach… it fulfills the book's theme, the collapse of the rational world for a decent man.

At the core of such fiction is the conviction that our lives will remain essentially mysterious to us—that as human beings we don't know what we are and cannot grasp our own experience.