Casualty spoilers follow for Saturday’s episode (14 March), which is available to watch now on streaming service BBC iPlayer and hasn’t yet aired on TV. This article contains storyline details that some viewers may prefer to avoid.

Casualty has aired a shocking cliffhanger involving Cam Mickelthwaite, as his role in Siobhan McKenzie’s harrowing rape storyline becomes clear. Siobhan has struggled to move forward after she was attacked by Chris Banfield, and she was frightened by the discovery that he recently showed up at the hospital to taunt her.

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As she reached breaking point last week, Siobhan asked colleague and clinical lead Flynn Byron to hurt her attacker Chris in an act of revenge.

Siobhan was serious about her request, as in today’s episode, when Flynn helped her to install a security camera in her house, she asked him again to take violent action against Chris.

Keen to help Siobhan feel safe, Flynn eventually agreed to track Chris down and hurt him – but he sternly warned her that violence will live with one forever.

With Siobhan struggling to see the men in the hospital as anything but predators, she pushed forward with the plan and broke the rules to give Flynn the home address of Chris.

Cam grew concerned about Siobhan’s wellbeing, and he was furious when he discovered that Chris had turned up at the ED recently. He raged at Flynn for not doing more to protect Siobhan, but he promised that he was handling the situation.

When Cam tried to reach out to Siobhan again, suggesting that he knows what she is going through, Siobhan snapped – saying that it isn’t the same thing as she did everything right in terms of reporting the abuse. She immediately realised that she had said the wrong thing, but Cam was completely devastated.

Siobhan later had an emotional encounter with the mother of a girl who suffered a fatal overdose, and she realised that taking revenge on Chris would be futile and only leave permanent scars.

She changed her mind about the sinister plan and tried to find Flynn to tell him, but Rida said that he’d left the ED a while ago. Siobhan feared that she was too late, and things got even worse when a male assault victim was brought into the hospital.

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As the paramedics took him inside, Siobhan looked at the man’s ID – and was relieved to find that it wasn’t Chris. Flynn then arrived back at the ED and told Siobhan that he hadn’t carried out an attack after all.

Siobhan explained that her reckless idea stemmed from rage, and she vowed to apologise to Cam. Unbeknownst to her, Cam found Chris’s picture and address in Siobhan’s office. Will Cam carry out his own revenge on Chris, and will he put himself in danger?