Eragon hurries home to mentally converse with Saphira about the hooded strangers. When she finds out, she has a major freak-out.
Saphira lashes her tail and claws the ground. In an effort to calm her down, Eragon climbs onto her back (seems perfectly logical).
Bad move, E.
Saphira launches into the air, with Eragon clinging to her back. They go so high that he gets frost on his eyelids.
Eragon tries to get her to land again, but Saphira is not listening. She keeps flying, and Eragon does his best not to throw up from all the wild motion.
Saphira flies into the mountains until it gets dark. Finally, she lands in a small clearing, and Eragon can at last climb down.
He's in rough shape. He's freezing, his muscles are cramped from hanging on for so long, and, worst of all, his inner thighs are bloody where Saphira's scales rubbed against his legs. And you thought riding a dragon would be fun!
Saphira is still in freak-out mode and refuses to take Eragon back. She's worried about the "murderers" (10.17).
Eragon has no choice but to go to sleep. Saphira at last curls around him, and the warmth of her body staves off the chill. She even puts her wing over him like a big blue tent. So sweet.
Eragon warms up, but he's worried about what might happen to Garrow and the farm if the strangers go to his home.