In The Clue of the Savant’s Thumb, Creek and fellow investigator Joey Ross (Sheridan Smith – Accused, Gavin & Stacey) are drawn into a complex case involving a secret society, seemingly supernatural events at a girls’ boarding school, and the miraculous disappearance of a body in front of three witnesses. Alan Davies says: “The new story has more than the usual amount of twists and surprises, and I'm very much looking forward to sleuthing again. I can't wait to join Sheridan Smith on set again; we're very lucky to have her. It's nearly 17 years since I first auditioned for the part; the duffle coat is always on standby, even if the periods of duffle-hibernation are quite long these days”.