Faith (Kirsty Mitchell) picks a terrible day to try to withdraw from the drugs she's been addicted to in recent Casualty episodes when she's roped in to working on her day off - and finds herself right in the middle of the drama when a snake goes missing somewhere in the department.
Faith has been self-medicating with pills to cope with her day to day life after being raped last year. Although she was able to tell boyfriend Iain (Michael Stevenson) about the rape, after he told her his attitude to drug-taking she didn't feel able to confide in him about her addiction and took the decision to flush the rest of her pills down the toilet.
In Saturday (May 27)'s episode the team are looking after a woman who's been bitten by a snake at an animal park and Stevie (Elinor Lawless) and Faith try to work out how to treat such a rare case as the woman's health goes downhill rapidly. Then complete horror sets in when they realise that the woman brought the snake in with her - and it's now vanished from her bag and could be anywhere.
Faith is struggling to cope with the day as it is. She's experiencing terrible withdrawal symptoms and people are starting to notice she isn't her usual self when she seems distracted and keeps making mistakes.
That's when the snake makes its reappearance, and Faith suddenly finds she has more to worry about than her withdrawal symptoms when she's bitten - and suddenly her life is in terrible danger.
Will the anti-venom (that Faith forgot to order) arrive in time? And will she give in to her addiction when she's offered drugs to deal with the excruciating pain?
Elsewhere, Jacob (Charles Venn) is still having trouble settling in as a member of the paramedic team and clashes with Iain when they go to a dangerous situation where an injured electrician is dangling from a tower block on a rope as sparks fly around him.
As Jacob insists on doing things his way he leaves Teddy (Milo Clarke) and Iain to struggle without him - with devastating consequences.
Jan (Di Botcher)'s ex husband Gethin (Robert Pugh)'s motor neurone disease begins to affect every aspect of his life, and Jan is at a loss about how to help him. She hits on the idea of taking him to the beach, where she meets someone who gives her some wise advice. But is a day at the seaside what Gethin really needs?
And after we learned previously that Cameron (Barney Walsh) is keen on Jodie (Anna Chell), he tries to impress her by being a bit more assertive at work - with very mixed results.
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