Julius, a magician posing as a simple Egyptologist, takes the siblings to the British Museum, where he tries to bring Osiris (the Egyptian god of the Underworld) into the mortal world.

Carter and Sadie are taken to Brooklyn by their uncle Amos, who tells them they are descended from a long line of magicians, beginning with the Egyptian pharaohs Ramesses the Great and Narmer.

They train in magic until the magicians' leader Iskandar dies and Michel Desjardins orders their deaths for collaborating illegally with the gods.

The siblings escape and form a plan to defeat Set — hoping to rescue their father and clear their names within the magic community.

The foursome heads to Set's hideout, where they learn the final piece of the spell they need from a dying Zia, the unknowing host of Nephthys.

Carter, Sadie, Horus, and Isis use the spell to subdue Set, although they stop short of completely destroying him because they realize his actions were dictated by a far worse enemy — Apophis, a much more powerful god of chaos.

[8] He had already written and published several books in the Percy Jackson & the Olympians series, which dealt with the interaction between Greek mythology and the modern world.

Carter and Sadie Kane, the titular characters, were inspired by two siblings he taught, as well as the fact that Ancient Egypt was a multicultural society.

[16] On October 2, 2012, a graphic novel version of The Red Pyramid, adapted and illustrated by artist Orpheus Collar, was published worldwide by Disney Hyperion.

[17] The Washington Post said that Riordan "begins [the book] with a literal bang" and "the pace never flags as the narrative cuts between Carter and Sadie.

[20] The New York Times's Bruce Handy was mildly critical of The Red Pyramid saying it had "eruptions of mayhem every few pages and exposition falling like hail", as well as "a sea of churning narrative".

He also commented that the book was "wholly satisfying while also setting the table for what promises to be a rip-roaring saga with nasty villains" and "engaging love interests.

"[21] Kirkus Reviews thought the story was similar to Riordan's other works like The Lightning Thief in terms of chapters, characters, and plot, but noted, "that's not all bad.