The entire trilogy.
After an encounter with Jamie, a bully from their past, Callum and Harry decide to seek revenge. However, everything changes when the bully discovers a magical stone that grants him powers.
A new villain named Mullac threatens the fate of the universe, and it's all up to Callum, Jamie, Bill, and the Time Veteran to stop him.
Callum is forced to tie up loose ends after bringing balance to the universe when he is confronted with the reappearance of The Menacer, his former kidnapper, and the unexpected return of Mullac, whom he thought was dead.