It took 13-year-old Isabel Sen and 12-year-old Jacob Gordon 7 ½ hours to read it through. Both had finished the book by early Saturday. They tell The Early Show co-anchor Hannah Storm their emotions were caught up in the spellbinding twists and turns of J.K. Rowling's book.
One very important character suffers a terrible death. "I sort of, like, gasped because I didn't expect that person to die," Gordon said. "But I just sort of in the back of my mind saw it happening."
What was mostly surprising to Sen was the way in which the death takes place: "I was surprised as to how they died. I didn't think that the person who killed them would kill them."
In the fourth book a student is killed, but Tina Jordan, the senior editor of Entertainment Weekly magazine, said she doesn't think children were emotionally invested in him.
"This character is one who has enormous significance for them," she said. "The death scene itself will be hard for younger children to read because it's very graphic and brutal. There's also a funeral afterwards which is extremely emotional."
Sen also didn't expect to feel sorry for Lord Voldemort, as more about his past is revealed.
"We didn't know much about him before," she said. "It almost made me feel sorry for him. Then I remembered this is Voldemort we're talking about."
As for the similarities the evil character shares with Potter, Gordon said, "I wasn't surprised about that, sort of, because she sort of told the readers in the last book and maybe the fourth and third books. But you find out a lot more about Voldemort, and you see why he became evil and how."
Unlike some previous books, Jordan noted, "The Half-Blood Prince" is dark.
"It has very serious themes," she said. "There are things that will certainly scare children in it. Especially younger children."
It is clear Potter is the chosen one who can kill Voldermort so it is up to Dumbledore to teach the young wizard how to do it.
Jordan explained, "Dumbledore is showing him how Tom Riddle became Voldemort so that Harry would have a better chance to defeat him. You realize that as each chapter goes by."
But that is not the only thing in Potter's mind. At 16, he now has interest in girls, one in particular, even to the point of falling in love.
"I wasn't all that surprised," Sen said about his choice of a girlfriend, trying not to give plot details away. Gordon adds, "I couldn't really find anyone else."
But what was surprising to him was all the kissing in the book. "I did not see it coming. When they came out of Quidditch and she just put it out there."
Jordan said for her 10-year-old daughter, those romantic scenes were just "gross."
"It's disgusting," that is what Sen said her 11-year-old sister said about their first kiss.
But in essence, what makes this book such, Jordan said, is its realism.
"It tapped into fantasies for children. Not only is it this perfectly imagined fantasy world, the kids are like real kids. Now, when you're reading 'The Chronicles of Narnia,' those are fabulous books, but the kids aren't like kids today."