Over the course of my investigation I hit many dead ends, whether that was trying to track down specific individuals who had changed their names, or court records which had been lost. Myself and my producer Seren Jones spent so much time on the streets, in the archives, on calls and chasing leads. Sometimes it felt as though every door closed just as quickly as it opened. Other times we made devastating discoveries, hearing ex-members in both the UK and US detailing their allegations of abuse and mistreatment that spanned far beyond the timeline of 2019.

Ex-members spoke of the IUIC practice of “standing up” members who were in trouble with leadership. Members who were viewed to have “sinned” claimed to me that they were asked to stand in front of the congregation and were berated for up to half an hour — for incidents such as wearing clothing that wasn’t considered “modest” enough or “fornicating” (sex outside of marriage is not accepted within IUIC).

Many ex-members report feeling as though their lives were put on hold during their time within IUIC. That their vulnerabilities were taken advantage of. They found themselves existing in a whole new world; where there were strict dress codes, strict codes of behaviour, and consequences if you diverged. When they left the organisation they said they felt ostracised and completely locked out of their former community.

Waking up from the experience was disconcerting. As one former IUIC member, Gina Blue, told me: “ When I was separated from them, it was like somebody took a blindfold off of me and everything that I experienced and all the stuff that I just put to the side, all the red flags came to the forefront. It was almost like a movie.”

When contacted for comment, IUIC London told Glamour UK that allegations that the church holds misogynistic, anti-white, anti-LGBT, and anti-semitic views are “fundamentally false”, as are the allegations that the church is a cult that preys on vulnerable people, and isolates and ostracises its members. The church said that “IUIC London teaches the commandments throughout the bible. It is a commandment to comply with the laws of the land that we reside in according to Romans 13:1-2 (KJV)…”

The friends and family of Joy Morgan believe that she would have eventually been one of the members who would have chosen to leave the world of IUIC behind. That she would have re-entered the mainstream world.

We will never know for certain what Joy might have done, but throughout the course of this investigation, my conviction in the importance of telling her story has only sharpened. One of her best friends from school, Agnes Embi, told me all about her. How she loved to laugh, that they made up dances together, cooked together. “I was the responsible one. She was carefree,” Agnes said. Joy may have been carefree, but the story she left behind is anything but. It was a story that demanded answers.

The Missing Sister is available on BBC Sounds.