Ruby Redfort: supercool secret agent, code-cracker and thirteen-year-old genius The fourth book in the scarily awesome Ruby Redfort series, from former Waterstones Children’s Laureate and multi-million-copy bestselling author Lauren Child. This time Ruby must pit her wits against a seemingly invisible foe.

How do you set your sights on catching a light-fingered villain if you can’t even see him…?