"When Nothing Else Matters" is the 901st episode of Casualty and the 34th episode of the 28th series. It was preceded by "Only the Lonely" and followed by "Carrot Not Stick". This episode was directed by Ashley Way and written by Mark Stevenson.
Fletch attempts to build bridges between a feuding father and son following a car crash in which another sibling suffered a serious head injury.
Cal tries to impress Lily as they work together on a patient who appears to have used the internet to diagnose himself with a brain tumour, and Jeff agrees to cover for Ash’s daughter, Ella, after she suffers an allergic reaction to ketamine at Robyn’s house party.