Casualty series 40

Indie's last shift sees her accompany Teddy to a house where a disturbance has been reported. Getting in through a window, she finds a woman who has lost her clozapine and is having a mental health crisis after being spooked by the noises from the pipes. Indie is able to calm her down. Arlo, who lost his girlfriend weeks earlier after she took tainted drugs, claims he is clean but the staff are suspicious when he claims to be in pain. When an injured dog walker is also in more pain that she should be, Faith suspects patients are being told they've been given morphine by paramedics when they haven't. Cassie brings in a friend, Steph, who has taken drugs. Nicole realises Cassie is dealing and takes her supply, but she goes back to the dealers, even after learning they have been forcing Steph to sleep with men. Siobhan looks after an underage student with a head injury who later dies after Stevie realises he and other teens have taken contaminated ecstasy. Rash messes up booking a show for him and Sunny. Rida suggests they accompany the nurses clubbing but they end up going back to Sunny's instead. Indie meets an old friend, Badger, at the club who offers the group pills. Rida, Teddy and Jodie take a young man they found collapsed to the hospital. Siobhan realises Teddy and Jodie took the pills and insists they stay in for observation. Teddy is unable to get hold of Indie and Badger.

Indie wakes up in Badger's flat and finds him unconscious after taking one of the pills. She look after him until Iain and Teddy arrive and he is taken to ICU. Jan suggests Indie apply for a vacancy at Holby. A man is brought in with stab wounds and a head injury. His wife claims he was attacked by an intruder but both she and her young son let slip that she argued with him beforehand. After he dies in Resus, Nicole realises the wife is on drugs and she admits she attacked him when he tried to take their son and leave. Nicole supports Cassie at Maggie's funeral and convinces her to come and stay with her. Dylan makes a number of proposals including an amnesty where drugs can be handed in to be destroyed. After he admits cannabis could help a Parkinson's patient, Flynn relaxes his attitude and supports the idea. Iain and Teddy are called out to the home of a cancer patient who has died. Iain is suspicious of Teddy when the patient's daughter finds his morphine is missing but it turns out the patient took it himself, leaving a suicide note. Teddy has however taken some of his medication after his heart medication ran out and Iain tells him to hand it in at the pharmacy. Jacob asks to borrow money from Iain. When another of Jacob's patients hasn't been given morphine and Flynn reveals hospital grade morphine has been found on the streets, Faith wants Iain to tell Jan.

A young woman is brought in after jumping out of a window for a bet while high on ketamine. Cam has to put a catheter in and Rida arranges a chaperone but he continues after she is called away, leading to the patient accusing him of sexual assault. Siobhan chides Rida for not supporting Cam. The patient later withdraws her complaint and it turns out the ketamine has caused bladder problems. Cam had agreed to have a drink with Indie but heads home instead. Jacob and Teddy are called out to a swimming pool to treat Sandra, an older woman with breathing problems. Teddy realises there is a chlorine leak and has the place evacuated. Sandra is taken to hospital but dies. Alex, a lifeguard who accompanied her, realises he knows nothing about her family despite speaking to her regularly. Iain and Tim arrive with HART and learns a staffmember is missing along with a young girl whose stepmother Shelly was organising a birthday party for her. Iain and a partner rescue the staffmember but Iain goes back for the girl against orders and they both have to be rescued. Shelly reflects on how she was only married to the girl's father for two years before he died. Nicole and Ngozi look after a new mother with an infected caesarean scar and realise the baby has cateracts. Obi tells Ngozi he is home alone all the time and wants to go back to Nigeria. Flynn tries to get away to meet someone at 4.30 but arrives at the cemetery to find them gone. Iain confronts Jacob about the drugs and he reveals he has taken a second job selling pizzas to buy Blake's meds. Faith reports him to Jan anyway.

Nicole has arranged for Cassie to stay with a friend in Newcastle and leaves her alone while she goes into work. With Jacob on administrative duties, the other paramedics are called out to a multi-storey car park where a young motorcyclist, Fraser, has become trapped under a car. Even though Iain gives him two doses of morphine, he is still in pain when he is dragged clear. Teddy finds Cassie with a head injury nearby. Nicole realises Fraser was coerced into deliberately running her over. Cassie is rushed into theatre with a subdural hematoma. Rash and Rida treat a woman with an infected burn. She admits she left her family behind to go on holiday with friends and fell asleep next to a hot cyclinder. Sunny advises Rash on medication. Ngozi gets frustrated with a man with heart problems who is desperate to get back to work, pointing out none of his colleagues have asked after him and saying he needs to find a life outside work. She tells first Obi and then Nicole that they will go back to Nigeria. Nicole tells her that her mother put her in care at four. She asks social services for details of Cassie's parents and also her own file. Rash arranges to meet Sunny's son Jake. Iain finds evidence that the morphine issued to the paramedics is fake. It is revealed that Sunny is replacing it with saline.

Jan tells Sunny about the fake morphine. Iain and Teddy bring in a patient who is showing signs of an overdose but has actually been stung by a scorpion, who is found in the ambulance. Sunny gets the dosage wrong for the anti-venom but it is corrected. The patient suspects the scorpion was in a box of shoes she bought from China. Flynn treats a pregnant woman for gastroenteritis. When her husband turns up, the woman's friend tells Flynn she left him after he was violent towards her. Flynn stalls the husband so the pair can leave, then learns she walked out on him without explanation, emptying their bank accounts. Faith convinces Iain to attend couple's counselling but he just goes through the motions. Cassie's mother Vicky turns up and Nicole argues with her, leading to ICU head Lauren Maddox banning Nicole. Ngozi helps Nicole track down her mother Tina. Sunny admits to Rash that dealers bought Jake presents and then threatened him if she didn't supply them with drugs. She tips them off to steal a delivery being transported by security guard Terry, which leads to Terry being dragged under a vehicle. Rash and Jan tell the police and Sunny is arrested.

Nicole goes to Tina's house in Newcastle and is initially mistaken for a district nurse; Tina's mother Ruth had a stroke. Nicole eventually admits the truth and Tina throws her out. She comes back the next day and explains Nicole's father was violent and she was left with no support after he died in a motorbike accident. She ended up in a diabetic coma, woke up a month later to find Nicole was in care and never took her back. Her "mother" is actually her mother-in-law; she is married with three sons. Nicole decides against staying in contact. Holby receives another influx of patients who have taken contaminated drugs. A reporter highlights Cassie being a drug dealer, leading to the mother of one of the patients arguing with Vicky. Tests show Cassie is brain dead but Flynn opposes turning off life support. Dylan learns he feels guilty for convincing Claire to withdraw life support from their infant son and convinces him the case is different. Nicole arrives back in time to see life support turned off. Rash visits Sunny in prison but she refuses to give the police any information, worried about retribution against Jake.

Iain accompanies ambulance crews to the court house where both Sunny and her lawyer, Mei, have been shot. Rash insists on leading the team treating Sunny, who has internal bleeding into her lung. Jake visits with his aunt Danique, blaming Rash. Sunny insists on giving a statement to DCI Ahwalia before surgery, giving him the name of the man who shot her and attacked Terry and the location of a burner phone. She is later reported to be recovering. Joel Hannigan is brought in with an infected abscess; he was allowed to remain undercover after Ngozi nearly exposed him but is taking drugs and shows more loyalty to the gang than the police. Flynn and Ahwalia fail to talk him round. A young man is brought in with ethanol poisoning after drinking poorly made home brew. Ngozi gives him brandy to control the symptoms until he can be given the antidote. Nicole learns it is Ngozi's last day and fails to turn up to her farewell, where Cam and Indie kiss. Iain hears his mother has died, telling Stevie but not Faith. Three days later, Iain and Tim meet with Ahwalia to accompany him in raiding the home of Duncan Yates, the head of the drug operation.

The police raid sees Yates' nephew Bradley having his arm cut off when he tries to stop them cutting the door down. Iain and Tim look after Yates' wife Imogen when she has an angina attack but Iain leaves Tim to investigate a crying baby only to find it's a toy, with Tim being stabbed by Yates in a failed escape attempt. He recovers in hospital. Stevie tells Faith about Iain's mother. Iain suggests he's only with Faith because he wanted to fix her. Flynn looks after a schoolgirl who fell off a chair while drunk. He has a liaison with her mother and misses the fact the girl has a bleed on the brain, with her needing emergency treatment. He admits to Dylan that using sex to cope is unhealthy and phones Millie. Cleo Hainey goes into labour, having got off the drugs, and Rash, Nicole and Jodie deliver a baby girl. She decides to keep the baby, naming her Judy after mishearing Jodie's name. Nicole decides to go to the airport to say goodbye to Ngozi and Obi, with Siobhan driving her, but arrives to find Ngozi has been drinking heavily, fallen after choking and suffered a severe head injury. She is rushed to hospital where staff try and revive her.

Resident doctors Matty Linlaker and Kim Chang join the team. Dylan refuses to act as mentor so Matty is assigned to Flynn and Kim to Stevie. A number of casualties are brought in from a fire at a wedding. The groom has severe burns while the bride has been trampled and is arguing with her daughter. Matty fakes a failed attempt to reconcile them. Kim treats a young pregnant woman bitten by a dog and twice hits the alarm for help with minor problems but later diagnoses her with scurvy caused by poor diet. She also treats a woman with sunburn who tans to make herself feel better. Faith tells Stevie that Iain has moved out. Dylan admits to Stevie that he dated a Sarah Linlaker at medical school around the time Matty was conceived. Stevie quizzes Matty about his background and learns his mother is called Sarah and dropped out of med school when she fell pregnant with him. Kim takes over Ngozi's locker and initially thinks she's dead until Nicole shows a video call with her. Matty befriends Claude, a homeless man with breathing difficulties. Claude doesn't appear when called and Matty later finds him collapsed, failing to resuscitate him. He makes an anonymous report to the CQC criticising the department.

A school roof has collapsed, leading to multiple casualties. Teddy and Jacob are among the first on the scene and Teddy convinces PC Ashley Sullivan to let him take charge, finding three of the missing casualties. A boy at the hospital, Freddie, is reunited with his friend Xavier, who Flynn finds has swallowed a mass of hair and was being bullied by a missing student, Mari. Xavier admits he saw where Mari went and she is found badly injured. Freddie cuts ties with Xavier. Stevie and Kim go to the scene to look after a younger student, Oscar, who is trapped. Kim ends up trapped with him and Stevie has to talk her through performing a finger thoracostomy. Faith finds a teacher has a girl's passport and suspects he was trying to run away with her. In fact, he was sending her to an aunt in Spain to get her away from an abusive relationship. Siobhan suspects Faith is menopausal but tests show she is actually pregnant. Nicole collects Ngozi from rehab and drives her to her new job in Bournemouth (Obi is back in Nigeria) where they say their goodbyes. Matty learns the staff are having a collection for Claude and withdraws his complaint. Ashley invites Teddy for a drink. Dylan sees Matty discard a mouth swab and purloins it for a DNA test.