Michelle Collins guest stars as the distraught mother of Simone, a young victim of a college shooting incident, in this feature-length first episode of the new series of the long-running medical drama. Holby City's laid-back staff nurse Donna is catapulted into the Emergency Department (ED) to help out during the traumatic events, while new nurse Mads joins the team as its latest regular. She's struggling to understand the stronger regional accents of her colleagues in her first job since leaving Pakistan, with serious repercussions. Two patients are admitted separately after being shot with ball bearings fired from an air rifle, but Noel's discovery of sinister footage on the internet suggests the two cases may be linked and more attacks are imminent. The incident comes to a head at Holby College, bringing terror into the heart of the fully stretched ED.