Nico's Revenge

Hades has stolen the young and the beautiful Sapphire Portman, the daughter of Poseidon. This angers Poseidon. Sapphire has endured years of punishment inside of Nazi Germany. While being one of Miss Peregrine's young wards. Nico di Angelo is ordered by his ymbryne, also Sapphire's beloved "adopted" mother, Miss Alma LeFay Peregrine, to find the young girl.
Once he finds her, he must bring her back home to the loop. Many things get in the way of his plans and he ends up back at Camp Halfblood while Sapphire is back in Cairnholm. While at Camp Halfblood, Chiron speaks to Percy and Nico about what has happened to Sapphire. Both boys set out on a mission to speak to Hades and Poseidon.
Back in Cairnholm, Miss Peregrine finds out about the situation and orders Millard Nullings to search for Nico.