As Ammut begins to form, Frobisher demands KT's key - but where is it? Eddie and KT find it on Willow, and realise the purpose of the keys. Jerome explains his feelings to Joy in a letter. But Joy won't read it.

The Touchstone of Ra catches up with the students of Anubis house on the eve of their graduation as they encounter a new group of underclassmen and a mysterious stone that leads them on a quest to save the world from evil. In the Touchstone of Ra, the residents of Anubis House are nearing the end of their final term when their celebratory mood is cut short after a group of underclassman unexpectedly move into Anubis house, and a trip to an Egyptian museum leaves the group with a strange stone in hand. The Sibunas are confronted with their greatest challenge yet as they set out to decipher the secrets behind the touchstone of the ancient Egyptian god, Ra. As the power of the stone begins to cause chaos, it's up to leader Eddie Miller and the Sibunas to solve the mystery before it's too late. As the mystery unfolds, the Sibunas learn that not everyone is as they seem, and there's only one among them who can save them from the powers of the stone.