Malcolm is a talented healer, being able to cure almost any disease/poisoning; however, after one of his patients, a 15 year old boy, dies from a rare reaction to a cure for a simple fever, a rival healer accuses him of having let the boy die. After people began to avoid him and show hostility toward him, he fled to the mysterious Grimsdell Forest where he knew nobody would follow, and surrounded himself with strange apparitions like the Night Warrior; sounds that come from all directions; and multiple warning signs. He began taking in disfigured and deformed people whose villages didn't want them anymore, including Trobar and Luka.
After being driven out of Castle Macindaw, Orman recruited Will and Xander to bring him to Grimsdell Forest in an attempt to get the help of who they thought was the dark sorcerer Malkallam. Malcolm willingly helps Orman and is open and friendly to the three men. Malcolm becomes a regular ally and plays an important role in the book Halt's Peril where he saves Halt's life against all odds by giving him a common cure to a poison.
He also plays an important part in the battle for Castle Macindaw, providing a distraction that enables Horace and Will to attack the other side of the castle. It involved conjuring up the Night Warrior, the use of explosives, as well as getting his people to bash together saucepans so that it sounded as if a whole army was massed, ready to attack the castle, while the real attack was coming from another side.