The Sorcerer in the North
by John Flanagan
The book starts off with Will (a Ranger) rescuing a dog that he finds wounded on the side of the road, injured by a spear. Will then goes on to Castle Seacliff, the castle he has been assigned to and has a meeting with the Baron of the Castle Seacliff. After the meeting, a group of Skandians attempt to raid the castle and Will makes a deal with them: If he gives them food and water, the Skandians will leave. Before the Skandians leave, Will captures the man who hurt his dog and hands him over to the Skandians to become a slave.
Will is assigned to a mission to find out who the mysterious magician in Grimsdell Wood is and to stop him from terrorizing the castle of Macindaw. Will goes under disguise as a jongleur; somebody who acts as a jester but doesn't serve a king, going around the kingdom entertaining for money. He does this because people tend to trust jongleurs, whereas people often clammed up around Rangers, due to the mystery surrounding their position. This would, in turn, help him to get information on Grimsdell Wood. Will travels to Macindaw, where their Baron, Lord Syron, has been poisoned and is now in the hospital. His son Orman has taken over the castle while his father is ill, but Orman's cousin Keren has been trying to take over as Baron, but Will does not know this yet. Will rides to Grimsdell and sees the Night Warrior, one of the ghosts in Grimsdell, and flees in fear on his horse Tug.