"Mobile" is the 1031st episode of Casualty and the 27th episode of the 31st series. It was preceded by "The Good Samaritan" and followed by "Five Days". The episode was directed by Alex Jacobs and written by Mark Catley. The events of this episode take place on 11 March, as they're a direct continuation of those shown in the previous episode.
David takes a heavily pregnant Robyn to a graveyard, and makes a candid confession about his mental state while visiting his brother George's final resting place. However, any further progress is halted when Robyn suddenly goes into labour. Duffy, Max and Charlie rush to find them, and manage to get Robyn and her premature baby back to the ED. David admits he needs help, and takes temporary leave from work.
Meanwhile, on the booze bus, Jez manages to impress Louise with his compassionate attitude toward an avid gamer who was mugged, losing the mobile phone on which he kept pictures of his late daughter. This brings them closer together, and they share a kiss back at the ambulance station.
Back in the ED, Lily has serious concerns about a 12-year-old girl who seems to be exhibiting classic symptoms of drug withdrawal. However, it soon transpires that she's simply spending too long on technology, but Gemma had already accused the father of much worse.