Abraham, Rosita, Tara, Glenn, Maggie and Eugene drive towards D.C. in the school bus. Tara teases Eugene about his mullet, but Eugene's mind is elsewhere. He evades Maggie and Glenn's questions about his plan to end the walker epidemic. Then after a sudden mechanical failure, the bus skids out of control and flips onto its side. Walkers converge on the wreck.
In a flashback, Abraham furiously pounds someone's face with a can of food in a supermarket aisle. Bloodied bodies are littered all around him.
Back in the present, Abraham's crew fights off the walkers swarming the overturned bus. Tara guards Eugene inside and then arms him with a knife so they can join the fight. "I know it sucks and it's scary, but it's time to be brave," she tells him. Eugene watches in terror as the rest of the group fights off walkers. Finally, he stabs a walker to save Tara.
After the group kills the walkers, the bus erupts in flames. Eugene suggests they double back to the church. "We don't go back!" Abraham shouts.
As the flashback continues, Abraham calls out for his wife, Ellen. He finds her hiding behind a supermarket cash register with their two children.
Back in the present, Abraham's group camps in a bookstore overnight. They build barricades and start a campfire. Abraham joins Glenn, who's keeping watch, and thanks him for coming to D.C. Glenn urges Abraham to rest.
Later that night, Abraham and Rosita make love. Rosita catches Eugene spying on them but she and Abraham are used to it and carry on. Tara also catches Eugene spying. He admits to Tara that he sabotaged the bus because he's afraid of failing when they get to D.C. "If I don't save the world, I have no value," he says. Tara thinks what he did was screwed up, but reassures him that they're his friends and offers to keep his secret.
In the flashback, Abraham reassures his family that they're now safe. But they cower and refuse to come near him. He looks down at his hands, which are covered in blood.
The next morning, Rosita suggests to Abraham that they stay put for another day. Abraham, intent on reaching D.C., shoots down the idea as well as Maggie's suggestion that they sweep the town for supplies. Maggie insists they need to find water, but Abraham points to a fire truck parked across the street. "Just so happens it's got 500 gallons of water on it," he boasts.
Abraham tries to start the fire truck, but it sputters to life for only a moment. As he makes repairs, walkers stream out of the firehouse. The group fights the herd hand-to-hand until Eugene, mounting the truck, sprays the remaining walkers down with the fire hose.
In a flashback, Abraham wakes up in the supermarket to find that his family has fled. "Don't try to find us," reads a note from his wife.
Abraham's group idles in the middle of a road as Abraham fiddles with the fire truck, which has broken down again. They're hit with a powerful stench: a large herd of walkers has infested a former slaughterhouse and is obstructing the road. Glenn suggests detouring around the herd, but Abraham refuses. "We can get through!" he shouts.
Abraham grabs Eugene to keep walking north. Glenn stops him, and a fight breaks out. Amid the chaos, Eugene yells, "I'm not a scientist! I don't know how to stop it."
As everyone stares, Eugene explains his original plan was to con people into taking him to D.C., which he assumed would be a potential stronghold. He admits to trying to slow their progress as they inched closer to D.C.
Abraham furiously punches Eugene, who collapses unconscious onto the side of the road. Rosita glares at Abraham as Maggie rushes to Eugene's side. Abraham falls to his knees and cries.
In the flashback, Abraham finds the bodies of his wife and children, torn apart by walkers. He puts a gun in his mouth. But before he can pull the trigger, he sees Eugene running down the street with walkers in pursuit. Abraham kills the walkers then turns to leave. Eugene begs him to stay: "I have a very important mission," he says.