A day at the beach becomes a lesson in sibling bonding for Gideon in this magical picture book. Every summer, Gideon and his younger sister Audrey build a sandcastle together. But this summer, everything changes. Gideon decides to build the most spectacular sandcastle anyone on the beach has ever seen. And he's going to do it on his own--without any help from his sister. But much to his surprise, Gideon discovers that building together is more fun and that everyone has their own unique talent when it comes to creativity and imagination, even Audrey.

The Doctor (William Hartnell), Ian (William Russell), Barbara (Jacqueline Hill) and Susan (Carol Ann Ford) find themselves stranded in Aztec times when the TARDIS is trapped in a tomb. Proclaimed a goddess by the Aztec priests, Barbara attempts to change the course of history by forbidding the human sacrifices which are part of the Aztecs' religion. It is up to the Doctor to find a way back into the tomb and recover the TARDIS, before the priest Tlotoxl (John Ringham) unmasks Barbara.