Fireworks And Darkness — Natalie Jane Prior

the temperature in the room dropped, like the bitter cold before a storm, and the smell of magic gathered like a mist. then the windows rattled, the floor shook and the paper stars and firework cases and all the trumpery tackle of Casimir's trade suddenly lifted off the shelves and whirled around him in a blinding, stinging storm... Simeon Runciman is a firework maker who used to be a dark magician; a difficult man with a dangerous past. His son, Casimir, has always known part of the truth about him. But when Simeon's enemy, the sinister magician, Circastes, reappears in their lives intent on revenge, Casimir is caught in a web of murder, deceit and magic. Forced to fight for his own survival, Casimir must also confront the harsh truth of who his father is and what he has done, as well as the real nature of the magic that he wields.