Read this one. The global refugee crisis is the largest since World War II, but it's easy to see it only as a series of images: Syrians in life jackets landing on a Greek island. Frail boats, teeming, on the Mediterranean Sea.

This book tells you what living on the edge of that flight is like.

"City of Thorns" takes you deep inside the world's largest refugee camp, one that many people barely know exists. Author Ben Rawlence is a former researcher for Human Rights Watch, and he writes so closely that you feel as though you're following his subjects on foot through the dusty chaos of half a million people on the border of Somalia and Kenya.

This is the rare nonfiction book that pulls you into another world. The camp, even the weather, are characters of their own.

Actress Angelina Jolie, a special U.N. envoy for refugees, and actress Scarlett Johansson have visited Dadaab in Kenya, the book's promotional materials rush to say. But celebrities don't appear in "City of Thorns," and they're not needed there.

Instead, there is the young Guled, kidnapped from his classroom into the extremist group al-Shabaab to roam the markets of Mogadishu in Somalia and enforce its harsh code. "If you had music or inappropriate pictures on your phone you might be forced to swallow the SIM card," Rawlence writes.

Guled runs away to the refugee camp shortly after coming across his wife and watching, trying to hide his tears, as his colleague whips her for shopping during the time of prayer.

Then there are the seriously star-crossed lovers, Muna and Monday, one Muslim, one Christian, and the violent outrage that pursues them. There is Nisho, "little one," a market porter who visits his homeland, Somalia, for the first time while delivering goods. It scares him. He never let the truck out of his sight, Rawlence writes. "He talked to no one."

Famine. Corruption. Longing. Prayer. All are made almost tangible.

The book also strips back the bureaucratic sheen of aid organizations and governments, showing how sugar prices jump, plastic-sheet houses appear and spirits soar or fade with decisions made far away.

Rawlence notes more than once the $9,000-a-month salaries of United Nations workers in Dadaab while the refugees, who hustle for almost everything beyond their free food rations, are not allowed employment. The camp is temporary, after all.

In 2016, it will mark its 25th year.

Meanwhile, the refugees take phone calls from the few friends who got lucky and made it overseas, and then fiercely debate their own chances. One chapter is titled, "Italy, or Die Trying."

"City of Thorns" winds down to an indeterminate end, as shifting as its people. For refugees, the camp is a place where so much happens and yet little ever does.