Detective Daf Davies is called to deal with an explosion at a local train station; the obvious assumption is that ISIS has reached rural Montgomeryshire. There is no room to relax as Daf attends courses on how to deal with terrorists and dicovers a body.

Mae'r Ditectif Daf Dafis yn cael ei alw i achos o ffrwydrad mewn gorsaf drenau leol... a'r dybiaeth amlycaf yw bod ISIS wedi cyrraedd Maldwyn fwyn. Rhwng gorfod mynychu cyrsiau i ddysgu sut i ddelio a therfysgwyr, a darganfod corff, dyw Daf druan ddim yn mynd i gael llaesu dwylo!