Iz and Joe never get to go on school trips, especially not residential ones. They don't mean to get themselves excluded, but still no one ever wants to take them. Mia isn't usually included in anything. She just doesn't see the world in the same way that other people do. Helen doesn't know if she'll be able to go on the trip. Her brothers and sisters often don't leave her any time to herself. And Chris wouldn't have gone, either, if he'd known what he was letting himself in for. This particular trip will take them further than any of them had imagined ...