The Institute is in full swing as everyone is preparing for the wedding of Alec and Lydia. Lydia is getting final touches made on her wedding dress, the wedding decorations are set and Isabelle is trying to figure out a way to throw a traditional, mundane bachelor party for her brother - whether he likes it or not. During what should be a time of great celebration for many is far from it as they examine their relationships. Alec is struggling on two sides - his wedding is one of the biggest days in his life and his parabatai should be at his side, yet he and Jace are still at odds. Alec also continues to struggle with his feelings for Magnus, especially when Magnus won't give up on Alec. And as the Institute is buzzing with romance, Clary is desperate to work things out with Jace, but he is keeping her at arm's length.
Meanwhile, Jace, Clary and Magnus go looking for warlock Ragnor Fell to try and find the antidote to awaken Jocelyn.
18 year old Clary Fray, finds out on her birthday that she is not who she thinks she is, but rather comes from a long line of Shadowhunters - human-angel hybrids who hunt down demons.
When her mother Jocelyn is kidnapped, Clary is thrown into the world of demon hunting with mysterious Shadowhunter Jace and her best friend, Simon. Now living among faeries, warlocks, vampires and werewolves, Clary begins a journey of self-discovery as she learns more about her past and what her future may hold.