Loretta Wallis is a girl with an outrageous imagination that hijacks her mind at any moment. Can anything match it? After her family move to London they start seeing Aunt Doris, whose late husband Walter had been an inventor extraordinaire. Aunt Doris thereby keeps a secret which is perhaps too extreme to tell. When the secret is eventually revealed to Loretta and her brother Mark, Aunt Doris is unable to guess what will happen next. So it is that events spiral out of control as the dangers which result from our everyday lives become an ever-increasing threat.