Casualty spoilers follow for Saturday’s episode (24 January), 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 devastating twist involving Siobhan McKenzie, in the latest episode of the current boxset, ‘Learning Curve’. Siobhan takes centre stage this week as she vows to help save the hospital after a chaotic chain of events during a surprise inspection, but everything changes in a dramatic final scene…

New resident doctor Matty made a complaint about the hospital to the Care Quality Commission after his first shift. He later realised he had made a mistake and attempted to take back his comments – but it was too late, as in today’s episode, the CQC showed up at the ED unannounced.

Flynn and Siobhan were met by regulator Ceri, who explained that concerns have been raised following the death of a patient, and she would be carrying out a spot safety inspection as a result.

Ceri moved through the department, observing what was going on and asking questions, but things soon went wrong in the ED, giving her more cause for concern.

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Dylan clashed with Matty in resus when he asked the newcomer to find bolt cutters to untether a handcuffed patient – but Ceri noted that Matty had missed a training opportunity.

Things went from bad to worse as the shift continued; radiology suffered a technical failure, Kim lost a child in the hospital, and a patient’s life was at risk after Matty took the batteries out of a laryngoscope to help his fellow resident.

When Ceri asked Dylan for a replacement laryngoscope, he snapped at her for disturbing him during a procedure, rounding off what proved to be a disastrous day in the ED.

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Ceri officially triggered a full inspection, explaining that she would return to the department in 30 days to see if things have improved. Flynn rallied the team and promised that everyone’s jobs would be safe regardless – as he will resign immediately if they fail the inspection.

Later, Siobhan told Flynn to go to his daughter’s birthday party, offering to stay and take care of all the paperwork that urgently needed doing.

She worked into late into the night before deciding to walk home instead of using the money that Flynn gave her. Siobhan left a voicemail for Flynn – then in a horrifying twist, she was pushed to the ground by a mysterious stranger, with her screams heard in the closing seconds of the episode.

What has happened to Siobhan, and will she be okay?