Kavanagh begins his life patrolling the Wall. If he's lucky, if nothing goes wrong, he only has two years of this, 729 more nights. The best thing that can happen is that he survives and gets off the Wall and never has to spend another day of his life anywhere near it. He longs for this to be over; longs to be somewhere else. He will soon find out what Defenders do and who the Others are...
About what might be found when all is lost.