Life in New York has its own difficulties. At first Deo finds shelter on the floor of a squalid Harlem building, but eventually takes to sleeping in Central Park. His job, delivering groceries for an Upper East Side supermarket, pays him fifteen dollars a day, and he can’t reconcile himself to the idea of accepting tips, which strikes him as a form of begging. But in a surprisingly short time, and with the help of several New Yorkers, Deo rises from the gutter of penniless immigrant anonymity to heights he never would have dreamed of.

Kidder divides the book into two parts, and to say that the execution is lopsided is more a compliment to its first half than an insult to its second. The events summarized above comprise the first half of Strength in What Remains. The author recounts them with extraordinary immediacy, made possible by his decision to venture into Deo’s thoughts, fears, and memories, complete with physical details.

As Deo mounts the staircase to the plane that will carry him from Burundi to New York, for example, Kidder writes: “In Deo’s mind, there was danger everywhere. If his heightened sense of drama was an inborn trait, it had certainly been nourished. For months every situation had in fact been dangerous. Climbing the stairs a moment before, he had imagined a voice in his head telling him not to leave. But now he stared at the hills and he imagined that everything in Burundi was burning. Burundi had become hell. He finally turned away, and stepped inside.”

That Kidder maintains this intensity for nearly 150 pages is a dual feat of reporting and imagination. The breathless, harrowing story of Deo’s run through the jungle is packed with violence, pathos and just enough historical context to orient the reader without distraction. And by alternating chapters between Burundi’s horrors and New York’s indignities, confusions, and pleasures, Kidder cleverly ratchets up the narrative momentum.

In short, the unremitting first section plays like an action movie. The second, however, is more like a director’s cut, furnishing deeper historical context and fleshing out the resumes of supporting characters. It also makes good on the book’s subtitle, “A Journey of Remembrance and Forgiveness,” as Kidder accompanies Deo to Burundi and Rwanda to revisit the landscape of his childhood and retrace the path of his escape.

Not surprisingly, this expository section lacks the immediacy and artfulness of the preceding pages. The book peaks at its midpoint and, lamentably, plateaus. Still, this less action-driven interval wrestles with the interesting question of Kidder’s—and by extension, the reader’s—relationship to Deo. How are we to live comfortably after immersing ourselves in the squalor and desperation of Deo’s Burundi, not to mention the trials of his life in New York?

Kidder approaches this question cautiously and responsibly—which is to say, without any pretense of truly understanding Deo’s story from the inside. At one point, the author and his subject visit a Rwandan genocide memorial situated in a former school. Inside, the skeletons of the victims are displayed on tables, their dented and crushed skulls testifying to incomprehensible brutality. Looking at the bones, Kidder is unsettled by his complicity in what can only be called the tourism aspect of the tragedy, especially as a “group of white-skinned people with cameras” comes scuttling up the path toward the museum.

Gregory Beyer is a journalist whose work has appeared in The New York Times and the Los Angeles Times.