Whistleblower Simon Andriesz reveals how he unearthed evidence that US Commerce Secretary Howard Lutnick had concealed a business relationship with the paedophile financier, Jeffrey Epstein. The British broker, who worked at one of Lutnick’s Wall Street firms, made the discovery in the Epstein files, some of which were released earlier this year.

Mr Andriesz also speaks for the first time about the personal cost of disclosing what was going on inside one of the companies then run by Howard Lutnick and his decade-long battle with courts and regulators. And he reveals how Mr Lutnick's firm was keen to agree a $1m deal with the former Prince Andrew for introductions to wealthy individuals and sovereign institutions.

Presenter: Andy Verity

Image: Howard Lutnick

Last year a Parliamentary Report concluded that between 1949 and 1976, around 185,000 babies of unmarried mothers were put up for adoption in England and Wales, many of these by force. For File on Four, The Skewer’s Jon Holmes investigates whether he was one of them.

Jon Holmes has always known he was adopted, but was never very interested in searching for his birth parents until results of a recent DNA test proved he was of Irish heritage and his curiosity was piqued.

A large folder arrives from Warwickshire County Council and slowly Jon begins to unpick the story of his life and the world he was born into. As secrets of Jon’s past are revealed, a Parliamentary Report by the Committee on Human Rights is published detailing shocking and vivid accounts of mothers being forced into giving up their babies by a society that outcast and shamed them at every turn.

What will Jon discover about his own family? What truths will he uncover as he speaks to mothers forced into handing their newborns over, as well as fellow adoptees about the damaging and traumatic culture he was born into?

Government has always denied any responsibility and is refusing demands for an apology, but is that really the case?

As Jon slowly finds out more about his own past, he also investigates the impact of this era and asks where does responsibility for this societal culture lie… and can it ever be repaired?

Presenter: Jon Holmes

File on 4 Investigates concerns about how some strict discipline measures are being implemented in schools across England.

We discovered students internally excluded for around 20% of their lesson time, and some much longer. The Outwood Grange Academy in Wakefield put one pupil in an isolation booth for more than half of the academic year.

We hear from a mother in Devon whose son Taylor took his own life, weeks after he’d expressed his frustration at what he saw as his school, Ivybridge Community College’s punitive and illogical rules.

Presenter: Jane Deith

This programme contains reference to suicide and self harm.

If you've been affected by some of the issues raised in this programme you can find out more about organisations that can help by going to www.bbc.co.uk/actionline.

File on 4 Investigates how Immigration Enforcement officers are tackling sham marriages. Claire Jones follows Home Office officials as they apprehend people entering into, and organising fake marriages in order to circumvent the UK’s immigration laws. She discovers details of criminal gangs charging people up to £30,000 for a partner and 'marriage pack', a set of photos and documents designed to create a convincing back story of the fake relationship. After File on 4 Investigates asked the Home Office why more statistics are not available on suspected fake marriages, they have now committed to regularly publishing these numbers 'in due course'.

Presenter: Claire Jones

The Church of England is confronting difficult questions over a £100 million fund to address its historic links to slavery. Aleem Maqbool hears from clergy, historians and politicians as he explores the arguments over reparations, responsibility and whether the Church can make amends for sins of the past.

Presenter: Aleem Maqbool

Liv Nervo is one of the world’s most successful female DJs, who along with her twin sister, make up NERVO. She was starting a family with a man she believed was the love of her life - but at six months pregnant, she discovered he had been living a double life. She says she entered the relationship under false pretences and wouldn't have consented to sex had she known the truth about his other relationship.

What happened to her reveals an intense debate about consent, the law and a lesser-known form of domestic abuse called reproductive coercion.

G for guidance - this programme contains strong language.

Presenter: Alys Harte

Hair Strand Tests can show if parents have been using drink or drugs. Such tests play can a central part in Family Court hearings every year as judges decide whether children should go into care or not. Some barristers have been raising the alarm over the way the tests are presented and interpreted in the Famly Court. And, for the first time, File on 4 Investigates talks to mothers who nearly lost their babies – thanks to hair strand tests.

Presenter: Sanchia Berg

Image: Lead Senior Scientist Dr Ellie Menzies carrying out a hair strand test

As the government plans major reform of the England's Special Educational Needs system, File on 4 Investigates goes back to the floor, spending time with councils as funding decisions are made and with families trying to navigate a system in flux.

From home-schoolers in Whitley Bay to getting on board a school bus in Hackney, we'll hear about the challenges of delivering services to tens of thousands of children with SEN each year. As the number of young people who need extra support rises how will Councils balance their books?

Over a hundred schools have closed in England in the last five years. Analysis by the BBC’s Data team has shown that pupils with special educational needs have been disproportionately affected by school closures. These pupils made up 29% of those whose school has closed, which is higher than the national average.

We'll hear how the disruption of a school closing can affect those with additional needs, and their families.

Presenter: Hayley Clarke

(Thanks also to the BBC News Data Journalism team)

Police have dealt with scores of cases involving home-made 3D printed guns in the UK in the last three years. Data obtained by File on 4 Investigates from the National Crime Agency shows that criminals and extremists have attempted to manufacture the weapons.

We hear from police who successfully prosecuted a group who had manufactured printed firearms to sell on to criminal gangs. As Adrian Goldberg asks, how much of a threat are these printed weapons in the UK and what can be done to deter people from making them?

Producer: Paul Grant

Finance professionals who paid thousands for training courses in Dubai seemingly endorsed by a government official say they were duped by the British businessman behind them. Participants in the 12-week “accelerator” programmes say they provided little in the way of useful training, while the millions in potential investment offers promised to graduates never materialised.

File on 4 Investigates a trail of deception left by the British “finfluencer” behind the course.

Presenter: Yemisi Adegoke