Lyra lives in a different world where daemons (their souls) live with them and become best friends. When the person feels for instance angry their daemon turns into an angry creature like a lion.
Lyra the main character goes into a room where Lord Asriel is doing something she sneaks into the room and when Lord Asriel comes into the room to lots of people she finds out something called Dust which in their world is a magical light. So the book is about how Lyra and Pan (her daemon) become so interested about dust crash but could that be true?
She finds Gypsies and kidnappers and lifesavers. The Gypsies help her on there quest to the northern lights.
One of the lifesavers is Iorek Bjornison who is a Polar Bear once king of the polar bears. He has a fight with another polar bear who is now king and they've made a deal that the bear who won the match would become king.
I think his book is an extremely detailed and is a fantastic story and makes me grip so I can't put the book down. Even though it is very long it is worth reading. Out of 10 I would give this a 9. I would also recommend this book for years 3 (who want a challenge) and up. Whoever reads it will find it quite interesting and will find it long but also quite fun to read and you'll find it quite good to watch the film 'the golden compass'