"Strangers" is the 973rd episode of Casualty and the 12th episode of the 30th series. It was preceded by "Avoidable Harm" and followed by "Estranged". The episode was directed by Sean Glynn and written by Andy Bayliss.
Dixie and Iain are driving when a little girl runs out onto the deserted road ahead of them calling for help. Iain uses a tire and rope and goes down into the hole to help Jess. The mountain rescue soon turn up but just as they are about to take Jess out she faints. Iain and Jess are pulled to safety and brought into the ED. Lily treats her and there doesn’t seem to be any serious damage done. With Jess' BP still alarmingly high Dixie talks to her daughter Olivia and then manages to get the truth out of Jess and she reveals that she's been having blackouts. Lily manages to work out that Jess has a condition meaning that any movement in her neck of pressure on it means that she faints. Dixie delivers the new to Jess and her family and urges her to tell her boss as otherwise they risk lives. Whilst tidying out the ambulance Iain finds a box of medication and a bag that belong to Jess. Iain wants to just hand the bag back but Dixie is convinced that the anti – depressants means there is something more going on.
Matilda has a high temperature and so Cal brings her into the ED to get checked over. Ethan checks her over and says its most likely something viral but Cal notices a rash on her back. Everyone is convinced it is just an infection but to be on the safe side they put an IO line in which means drilling into Matilda's leg. As Matilda doesn’t react Cal becomes more and more worried about her. As Zoe and Charlie try to settle Matilda Cal and Ethan sing to her. As Matilda worsens and goes into Anaphylactic shock Caleb walks out as it's the only thing he knows how to do. Charlie goes after him and finds him in his car, they have a heart to heart which seems to make Cal seem sense. Matilda goes for a brain scan and everything seems normal. Back in the ED they have to preform a lumbar puncture to try and get to the bottom of why she is unwell. The lumbar puncture comes back clear but she is admitted anyway. As if things weren't bad enough Cal receives the results of his paternity test and it seems like hi isn't Matilda's father.
After Zoe tells the team that Alicia has left Louise isn't happy when Lily says she doesn’t know why and tells Zoe that Lily bullied Alicia. Lily then offers to do the birthday fund for Ethan but instead of going out and choosing one she gets 4 identical cakes so that they will deliver to the hospital. Louise comes in and tells Lily a few home truths about why Alicia left. Lily then gets an email that her mother found from her father. She tells Ethan about it and declares that she is a good doctor. Louise begs to differ and when Lily says that she was right to do what she did to Alicia, neither Ethan or Louise agree and they start having a go at her.
Lofty doesn’t seem to want to be around Jacob after he shouted at him and when he tries to tell him a story about a patient, Lofty isn't interested. Jacob then gets Big mac to tell Lofty that Zoe needs him in Connie's office and when he enters Jacob shuts the door behind him and post a note under the door and there is lunch for lofty on Connie's chair after Max and Iain ate his this morning. Lofty sees Jacob and when he says sorry Lofty tells him that's all he wanted in the first place, Jacob then apologises to Rita, Louise and Big Mac as well.
After the episode aired, some noticed that on Lily's computer screen, there appeared to be an email from "Jay Fauldron". Many fans speculated that this was Jay Faldren, but it left them confused as Lily and Jay have never appeared on the show together, as Jay left the show over 18 months before Lily first appeared. Furthermore, it had the subject "birthday", and at this time Lily was planning Ethan's birthday surprise, but Jay and Ethan had never met either.