Cass finds herself alone and disoriented in a dream-like world, while back at home she is in the hospital in a coma with Max-Ernest desperately searching for a way to awaken her.

When a mummy disappears from the local history museum while Cass and her friends Max-Ernest and Yo-Yoji are there, they try to solve the case in order to clear their names and, they hope, discover the Secret they have been seeking.