The investigation leads DI Cadi John to Gladwell Prison where Endaf Elwy has spent over a decade locked away for the murder of his young niece, Anna Williams. On seeing Endaf, Cadi's suspicion that an innocent man has been wrongly accused is confirmed. DS Owen Vaughan comes to realise that Megan Ruddock has become the serial kidnapper's latest victim, and Megan comes to see that she may have an unlikely ally in Dylan's young daughter, Nia. Show less