Casualty fans are caught off guard by 'INSANE' plot twist

Casualty fans were left shocked after the latest instalment of the BBC medical drama, where the whistleblower's identity was revealed to be the last person most viewers would have guessed.

*Warning Casualty spoilers ahead*

In last night's episode of last night's instalment of Casualty (which aired Saturday 18th May), we saw clinical lead Patrick continue to obsess over which staff member took part in the documentary, with all signs looking towards Rash.

But in a shocking turn of events, it was revealed that Rida is the whistleblower, with emotional final scenes in the episode.

'That was an insane plot twist about the whistleblower icl i was so convinced it was rash,' wrote one viewer on X (formerly Twitter).

While another said, 'And as for Rida, I knew she was good for an outside bet for being the whistle-blower, and I should have trusted my gut, but my god, did she break my heart at the end of the ep.'

Before adding, 'On a serious note, though, #Casualty showing two men dealing with their mental health in two completely different ways is so important.'

While another wrote, 'Noooo, I wanted Patrick to be the whistle blower so he can be booted out! Why, writers... why write it's Rida!'

While another guessed, 'I'm literally like two minutes in so no spoilers but the whistle blower is Rida isn't it??! I always thought she was good for an outside after what happened with Fern.'

And another wrote, 'Had a feeling Rida was the whistleblower. Felt for her though, heart was in the right place.'

And another said, 'Well I didn't think it was going to be Rida as the whistle-blower.'

Tune in next week on Saturday 25th May to find out what's next in store for Rida and the rest of the residents of Holby ED.

Casualty airs on BBC One — check out our guide to every episode for all the latest news and spoilers.

Viewers can also now tune into Casualty at 6 am on the day the show airs on BBC iPlayer .