Two years ago, local cartoonist Eroyn Franklin published Detained, a 26-foot, single-pane scroll about immigrants stuck in the confusing, indefinite limbo of an immigrant detention center. Detained folds up like an accordion—it can fit on a bookshelf or a bedside table—but hits hardest when it's fully unfurled, one long document about living behind bricks and bars, feeling stranded, frustrated, and bored.

Shortly after it was published, Franklin told me she chose that format to communicate the interminability of life in a detention center—the physical presence of the "book," stretching across a reader's living-room floor and into the next room, made the story land harder.

Last week, W.W. Norton published a similar experiment by Portland-based cartoonist and journalist Joe Sacco. The Great War: July 1, 1916 (Norton, $35) is a 24-foot narrative panorama of the first 24 hours of the Battle of the Somme. It was the bloodiest day in British military history, with 60,000 killed or wounded, many of them young men who'd never seen combat and had no idea what they were walking into. "I'm interested in flesh meeting the machine," Sacco said in an interview last week. "That's what the Battle of the Somme epitomizes."

That day—which some consider the bloody baptism of modern warfare—is infamous for its hideous mistakes. The British army in northern France had been pounding the German front with artillery for days. In a companion essay to The Great War, historian and journalist Adam Hochschild writes that gunners' ears began to bleed, and "the rumble could be heard as far away as Hampstead Heath in London." Confident that the enemy had been bombed into pulp, British general Douglas Haig ordered an ocean of young men to climb out of their trenches, run across a field, and finish off the few Germans left alive. Things didn't turn out that way. Many German soldiers survived, as did their machine guns, which opened fire on the British, turning the field into a slaughterhouse. But even after it was clear that there had been a miscalculation, with 30,000 casualties in the first hour—almost twice as many British soldiers were killed in that hour as all the American soldiers killed in Iraq and Afghanistan combined—British officers wouldn't pull the plug. Soldiers kept charging in waves and falling in piles.

Sacco poured months into studying photographs and oral accounts of the battle, trying to get the historical details just right—the bridles on the horses, the configuration of the latrines, just how the soldiers climbed up and out of the trenches (they used ladders). But his densely drawn scroll, teeming with bodies, has a surprising degree of human intimacy, giving The Great War the feeling of a grand Shakespearean tragedy. We know how it ends, but it's easy to get swept away in the telling and in the minutiae of each small step toward an awful inevitability.

Sacco has built a career out of chronicling armed conflicts and the human suffering that follows when governments and economies get into serious fights with each other. He's reported from and drawn about Palestine, Bosnia, Iraq, enclaves of African immigrants that washed up on the shores of Malta (where he grew up), and some of the most economically devastated places in the United States, including Camden, New Jersey, and the Pine Ridge Indian Reservation.

Sacco uses drawing—which shows some early influence from R. Crumb, but is tighter, riding the line between expressive and photo-realistic—to tell richer, more detailed stories than most journalists can. A newspaper might report that X number of people are living in a refugee camp, but Sacco shows us the shapes of their eyes and ears, their clothes, their kids, their cookware—he makes people seem like people.

Sacco rejects the myth of objective journalism, but doesn't call himself an advocacy journalist, either—he's just a journalist who admits that he has opinions. "If I'm sympathetic to a subject," he said, "I'll still see their warts and show their warts. I'm not an objective journalist—I'm an honest one." The Great War, he said, was an attempt to switch gears toward something more remote.

"I was thinking of it as a mass event," he said. Instead of highlighting the consequences for individuals, "I was thinking of the species as a whole in this context—the context of war." But every inch of the densely inked, 24-foot scroll contains a little anecdote of individuality: soldiers brushing and feeding the cavalry horses, standing in line for some soup and a roll, napping, contemplatively smoking pipes and cigarettes, writing what might be the last letter, shitting in trench latrines, shirtless and sweating in the summer heat as they haul around heavy equipment, loading shells into howitzers, smiling and doffing their helmets at a camera as they march to the trenches in the afternoon, trying to sleep in the trenches the night before the battle (some were so crammed in they had to sleep standing up), smiling naively while chugging their rum rations just before the charge, climbing over the trenches and into the field.

Then comes the carnage, which Sacco depicts with stark white space for smoke and pointillist explosions vaporizing dirt and body parts. Eight feet and a few inches later, we see the field hospital with its lines of stretchers holding mangled men. One of them sits up, his entire face wrapped in a bandage, with his arms straight in front of him like he's trying to fend off an invisible enemy. Nearby, tucked away behind an ambulance, a man leans against a tree and vomits. The final image is of men with their shirtsleeves rolled up, digging mass graves, while a chaplain looks on with a blank expression.

The intense detail of The Great War, all those individual expressions and gestures in that mass of soldiers, seems like homage. A friend, who's also an illustrator, said it reminded her of the Vietnam Veterans Memorial in Washington, DC—long, winding, crammed with visual reminders that every soldier, killed by every other solider, is somebody's kid.

Sacco explained the detail as "showing the organization, the amount of work that goes into a battle like this. You get to the front, go over the top, and all the orderliness becomes chaos, breaking over the machine of war." recommended