Casualty's Connie Beauchamp will make a life-changing mistake in this week's episode and it could have devastating consequences for poor Duffy.
Here's a full collection of the seven biggest moments you can look forward to.
1. Connie’s problems spiral out of control...
Having slept in her office because she’s too scared to leave the ED, Connie (Amanda Mealing) tries to prove herself to Ciaran while the team deal with the fallout from a terrifying prison riot.
Fed up with Ciaran making all the decisions, Connie becomes determined to exert her control – but can’t resist taking a pill in order to calm her nerves.
With Resus bursting at the seams, Connie starts to buckle under the pressure and her struggles don't go unnoticed by an increasingly-concerned Archie, who keeps a watchful eye on her. And unfortunately, it looks like Archie has every right to be concerned, as Connie is in absolutely no fit state to be making decisions of this kind...
2. ...And she ends up making a big mistake
Despite concern from both Archie and her ex-boyfriend Jacob, Connie is determined to plough on with her duties as she attends to Liz – who was stabbed in the prison riot.
When Liz accidentally dislodges her cannula and needs a saline flush, a disorientated Connie steps in. With disastrous consequences.
As a woozy Connie draws the saline, she unwittingly puts that syringe in the same dish as the lidocaine, both unlabelled. Needing an extra pair of hands, Connie asks Duffy to re-cannulate Liz, unaware of the lethal mistake she made earlier.
Duffy does as she’s told, but when Liz goes into cardiac arrest shortly after, Connie quickly realises her mistake. What has Connie done?
3. Duffy tries to prove herself...
Having made some difficult decisions over the last few weeks, Duffy is determined to prove herself in this week’s episode.
After bonding with an elderly patient called Stan, Duffy reminds everyone – and herself – of what a brilliant nurse she is when she spots something amiss with his symptoms and later persuades him to have treatment.
Devastated that Stan is refusing to fight his cancer diagnosis, Duffy reminds him of how much she has to live for in touching scenes and is pleased when he eventually agrees. Are things looking up for Duffy? Sadly not...
4. ...But a dark cloud looms over her future
Although Duffy is feeling more positive about her future in the ED when we leave her in Saturday’s episode, her new-found optimism is bound to be short-lived as the repercussions of Connie’s mishap play out in next Saturday's scenes (July 27).
Fans will have to wait and see whether Connie allows Duffy to take the blame for her mistake, but this story is certainly one to watch over the coming weeks.
5. Ciaran continues to make demands
Ciaran will continue to make Connie’s life a misery this week as he makes even more demands about the running of the ED.
Still unconvinced Connie is up to the task, Ciaran puts her to the test and keeps a close eye on her while she treats a patient in Resus.
Not content with leaving it there, Ciaran later bombards her with ways the department could be improved and criticises how she has handled the prison riot cases. How much more can Connie handle?
6. Iain is haunted by the past
Iain has more challenges ahead in this Saturday’s episode when he’s called out to the prison, where a young inmate has taken his own life.
The tragic circumstances naturally leave Iain’s concerned colleague Jan wondering how this will impact Iain's recovery and she’s on hand to give him all the support he needs. How will Iain cope with this?
7. Iain and Ruby make peace
Unsurprisingly, the devastating prison call-out does indeed have a big impact on Iain, but to everyone’s relief, he takes a sensible approach in the aftermath.
Having initially turned down Ruby’s invitation to the paramedics' meeting after work, Iain decides that he will attend after all.
Realising it could be good to talk about his feelings, Iain agrees to seek help at the session and even makes peace with Ruby in the process. Are things finally looking up for Iain?
Casualty airs these scenes on Saturday, July 20 on BBC One.
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