City of Lost Souls by Cassandra Clare is the fifth in the Mortal Instruments series and the middle book of the second trilogy. It continues the plot points set up in City of Fallen Angels. We follow several plotlines; Clary’s attempt to infiltrate Sebastian’s and Jace’s fortress, Simon and the Lightwoods’ McGuffin hunt in an attempt to find a way to separate Jace’s soul from Sebastian’s and the furtherance of Sebastian’s dastardly plan. Clare also explores some of the relationships in depth, notably Alec and Magnus Bane and also Simon’s relationship with Izzy. Given the work put into them, I am rather nervous for these couples for City of Heavenly Fire. What I liked Pacing. One of my complaints about the previous book was that the pacing was not great. This was considerably improved in City of Lost Souls. Having set up the plot threads earlier, Clare was able to run with them and keep the narrative flowing. Relationship development. I really loved how the relationships developed in this book. I became invested in Simon/Izzy, Maia/Jordan, Magnus/Alec. Their actions and how it impacted their relationships came across as very believable. I was particularly touched by Izzy’s backstory…