The war against Voldemort is not going well, even Muggle governments are noticing. Hermione scans the pages of the Daily Prophet, reading out terrible news. Dumbledore is absent from Hogwarts for long stretches of time, and the Order of the Phoenix has already suffered losses. And yet... As in all wars, life goes on. Sixth-year students learn to Apparate - and lose a few eyebrows in the process. Teenagers flirt and fight and fall in love. Classes are tough, though Harry receives some extraordinary help from the mysterious Half-Blood Prince. And all the while Harry searches for the full and complex story of the boy who became Lord Voldemort - hoping to find what may be his only vulnerability.