The NHS is sending patients with the most complex mental health needs to spend months or even years in specialist rehabilitation units, with the promise of helping them to recover. Adam Eley speaks to some patients who say they were sent to units sometimes hours from home, where poor care meant their condition got worse. Some experts say there is not enough oversight of the care provided. Credits: Reporter: Adam Eley Producer: Emma Forde Editor: Nicola Addyman

The high stakes cat and mouse game between police and darknet drug dealers Police say they are finally turning the tide on drug dealers selling on the darknet – a secretive part of the internet which has been described as like “online shopping for drugs.” The UK’s National Crime Agency says recent international takedowns of so called dark markets and arrests in multiple countries are a result of new techniques in cyber policing that is giving them the upper hand. However, BBC research suggests that police around the world have an uphill struggle on their hands as many dealers - known as vendors - have survived multiple market place collapses by operating across many different darknet sites. The BBC’s cyber reporter Joe Tidy and BBC data journalist Alison Benjamin journey into this hidden world to speak to vendors and buyers and uncover secrets of the trade The programme reveals the major role played by UK dealers in the global business which is estimated to be worth more than a billion dollars a year. Reporter: Joe Tidy Producer: Paul Grant Editor: Maggie Latham

How do you know if you’ve been recruited by a cult? Rachel Stonehouse investigates claims there are up to 2,000 cults currently operating in the UK. We talk to young people who say they were recruited on campus and a father who went to court to free his daughter from the influence of a harmful cult. Reporter: Rachel Stonehouse Producer: Michael Cowan Editor: Maggie Latham Researcher: Natasha Fernandes

With the murder of Sarah Everard shining a light on police vetting procedures, File on 4 reveals that thousands of officers have still not been re-vetted to standards brought in in 2006. As a public inquiry tries to establish what’s going wrong with our policing, Melanie Abbott talks to the women who say they’ve been betrayed by police officers who should have kept them safe and to officers who say sexism and harassment are part of the job. Reporter: Melanie Abbott Producer: Mick Tucker Editor: Nicola Addyman

An estimated £66 billion was spent by the government during the pandemic on paying towards the wages of people who couldn’t work, or whose employers could no longer afford to pay them. That’s around one fifth of the money the government spent on the response to Covid. It says 11.6 million jobs were supported by the furlough scheme. But the scheme also exposed the government to fraud and is expected to result in billions of pounds of additional losses to the tax payer. In September of last year, only after 6 months of the scheme running, HMRC was already estimating up to £3.5 billion of fraud and error in furlough payments. Now the scheme has closed, Paul Kenyon investigates businesses that claimed furlough money even thought their employees carried on working. Reporter: Paul Kenyon Producer: Anna Meisel Editor: Carl Johnston