The Red Pyramid recap

Carter and Sadie Kane, siblings raised apart, are reunited when their Egyptologist father performs a secret ritual at a London museum that goes disastrously wrong: he unleashes five ancient Egyptian gods and is imprisoned by Set, the god of chaos. Their uncle Amos takes them to a hidden mansion in Brooklyn, where they learn their family descends from the pharaohs and can host the power of gods. Carter becomes linked to Horus, the war god, and Sadie to Isis, the goddess of magic. Hunted by both Set's forces and the suspicious magicians of the House of Life, and aided by the cat goddess Bast and other allies, they race across the world to stop Set, who is building a great red pyramid in the American desert to unleash destruction on his day of power. At Phoenix they confront and overpower Set, but learn a greater enemy, the chaos serpent Apophis, looms behind him. Their father takes on the role of Osiris, lord of the dead, and the siblings return to Brooklyn to begin training other young descendants of the pharaohs, knowing far worse is coming.

Carter Kane has spent his childhood traveling the world with his father, a renowned Egyptologist, rarely staying anywhere long. His younger sister, Sadie, was raised separately by their grandparents in London and sees her father and brother only a couple of times a year. Their mother died years earlier under circumstances the children do not fully understand. As the story begins, the family comes together for a rare visit, with old tension between the siblings and a sense that their father is preoccupied with some private purpose he will not share.

At a London museum, the children's father performs a secret ritual that goes catastrophically wrong, unleashing ancient Egyptian powers and causing him to vanish, sealed away by a dangerous, fiery god. Their uncle Amos appears and hurries them to a hidden mansion in Brooklyn, where they begin to learn that their family descends from the magicians of ancient Egypt and that the old gods are real and now loose in the world. The family cat proves to be far more than an ordinary pet, revealing herself as a protective goddess, and the siblings, frightened and out of their depth, start to grasp that they have inherited strange and dangerous gifts.

The Kanes come to understand that they are hosting the power of Egyptian gods, Carter linked to the warrior Horus and Sadie to the magician Isis, and that the god of chaos who imprisoned their father intends to unleash a catastrophe. Pursued by that god's servants and distrusted by the House of Life, the ancient order of magicians who forbid the path the children are taking, they travel by magic across the world, gaining allies and learning to use their new abilities. A young enforcer of the House of Life crosses their path, and the siblings begin to piece together what they will need to stand against their enemy before his deadline arrives.

The children learn that the chaos god is raising a great red pyramid in the American desert, a monument meant to release destructive power on the day his strength peaks, threatening to devastate a vast region. Racing to reach Phoenix in time, the Kanes gather the artifacts and allies they need and press through mounting dangers, suffering losses along the way. Torn between the strict rules of the House of Life and the risky power of the gods within them, Carter and Sadie commit to the path of the gods and drive toward a final confrontation with the enemy who took their father.

The Kanes reach Set's red pyramid rising over Phoenix, where the god of chaos means to release enough destructive power to level much of North America on his day of ascendancy. Carter, channeling the war god Horus, and Sadie, channeling the magic goddess Isis, lead the fight, and rather than destroy Set, they force him down by learning and speaking his secret name, binding him to their will. In the process they discover that an even greater danger stands behind Set: Apophis, the ancient serpent of Chaos, whom even the gods fear, and who is straining to break free and swallow the world. The children's father, Julius Kane, does not return to them as before; instead he becomes the host of Osiris, the lord of the dead, taking a throne in the underworld and passing on a legacy to his children. Carter and Sadie also learn that the young magician Zia they met was a magical duplicate, and that the true Zia lies hidden elsewhere. Choosing the forbidden path of the gods over the rules of the House of Life, the siblings return to the Brooklyn mansion and resolve to seek out and train other descendants of the pharaohs, building a new house of magic to prepare for the rise of Apophis.