No longer having to impersonate his twin brother and following his successful closure rate for the major investigation team, puzzle setter John ‘Ludwig' Taylor returns under his new job title of crime scene consultant.After retrieving the files from storage, John is determined to find the incriminating information that led to Sinclair's death and James's disappearance.As the Cambridge Police Authority undergoes investigation in light of the Holly Pinder scandal, an unusual double confession at the theatre sees John take centre stage, where he must prove who didn't commit the crime. The case takes a turn when John meets a key witness who appears to recognise him – and not because he's Ludwig. Is there more to this witness than meets the eye?