In Fate's Instruments, picking up the story from where Paul's brother Jay left it in No Safeguards, Paul, an aspiring writer, marries Carlos, with whom he lived in Guatemala, and brings him to Montreal. Things go wrong from the beginning, and they break up. Then fate, in the form of a brain tumour, strikes Paul. He receives support from Jay, Lionel (himself a brain tumour survivor), friends, and the enigmatic Professor Bram. But it is Paul's exploration of his Vincentian childhood and new-found love that restores his equilibrium.