The Shadow in the North by Philip Pullman Synopsis 12

It all starts when Makinnon, a famous magician is in trouble. Some men are trying to kill him. Jim helps him escape, and he takes Makinnon to Fred and Sally. Fred and Jim do some private investigation, and much later on in the book, find its to do with a man called Bellman. Bellman is making a super killing machine. It looks like a normal railway carriage, but it has 6 thousand little holes, where bullets come shooting out 5 per second. Meanwhile Makinnon runs away and Jim goes out to find him.
In the end Bellman sets their house on fire. That night Sally had come to see Fred, Jim, Webster (Fred's uncle) and Isabelle (Makinnon's stalker) all were caught up in it. They managed to get everyone out except from Fred who went to save Isabelle, they both died.
Sally then reveals that she is having Fred's baby!