The crime-foiling quintet — siblings Julian, Dick, and Anne, their cousin George, and Timmy the dog — is back for a new adventure, this time at the ancient pyramids of Egypt. While visiting an archaeological exhibition curated by the siblings' dad, Bernhard, the Famous Five discover an amulet believed to contain secrets about a 5,000-year-old pyramid and the riches buried within. Bernhard and the kids travel to Cairo to deliver the amulet to the Institute of Antiquity, where, in a chaotic turn of events, Bernhard is accused of stealing it. Determined to prove Bernhard's innocence, the Five, along with their new Egyptian friend, Auni, put their investigative skills to work, chasing a shadowy network of cloaked agents all the way to the Valley of the Snakes!