The nightmare of past cases has forced Taliesin to retire as a detective. He takes part in a true crime podcast to keep his mind off the booze. When he and presenter, Mari, receive a link to a real life murder they realise that there are similarities with one of the cases they have been discussing. Who is the murderer and why does he look to the past for inspiration?

Mae atgofion hunllefus achosion y gorffennol wedi gorfodi Taliesin i ymddeol fel ditectif. Mae e'n cyfrannu i bodlediad am Droseddau Gwir a phan fo linc i lofruddiaeth yn ei gyrraedd ef a Mari, y cyflwynydd, mae'n sylweddoli bod yna debygrwydd rhwng y weithred dywyll a'r hyn maen nhw wedi bod yn ei drafod ar Ffeil Drosedd. Ond pwy yw'r llofrudd a pham mae'n e'n edrych i'r gorffennol?