Whatever Byrne had meant by his comment, the Lovett case emboldened many women to contact his radio show, telling stories that might easily have ended as tragically. It was a seismic moment in the state’s social history, the beginning of the beginning of the end, you might say, of the Catholic Church’s vice-like grip on Irish mores.

The Lovett case has haunted debates and referendums around sexual morality ever since, but the person at the heart of it all has tended to get lost in all the finger-pointing and posturing. In his gripping and unflinching new drama Ann, Ciaran Creagh gives moving insights into Lovett’s shrinking world by taking us through her final day.

“I’m of an age where I remember when it happened,” he tells me, “but I was a teenager then, and when you’re young, you just put things like that out of your mind. But the thing that really gave me the idea for this film was these articles Rosita Boland wrote for The Irish Times in 2018.”

To commemorate what would have been Lovett’s 50th birthday, Boland wrote a piece that sought to rescue Ann the person from the prevailing notion of a martyred victim: she also recreated in some detail the girl’s movements on the last day of her life. In another piece, Boland spoke to Ann’s former boyfriend Ricky McDonnell, who described their close and loving relationship and shed more light on Ann’s character and family background.

“What really struck about those articles was how Rosita Boland went into what happened on the day, which was not normally something you would see in a piece like that, and it just hit me. I started to wonder what would it have been like for a 15-year-old girl, on your own, with no YouTube to look up about having babies, so that you just wouldn’t have known. At that time, when you were 15, you knew nothing.

“It dragged me in, and I had to do it. I just kept thinking that if you were her, what would you do, walking around, with nowhere to go? And from day one, I knew that I was only going to write about those 13 hours in her life — she wakes up, her waters are broken, and then the end of it, when her parents come home from the hospital.

“When I went looking for funding, there was talk of elongating the story, but to me, that wasn’t interesting. I wasn’t interested in making a whodunnit, I wanted it to be about Ann.”

Ann Lovett is played by Zara Devlin, who delivers a compelling portrayal of a strong-willed and clever young woman who, in 1980s small-town Ireland, has run out of road. Eileen Walsh is Ann’s mother, Patricia, Ian Beattie plays her father Diarmuid, owner of a Granard pub that rarely seems to open, and Senna O’Hara is Patricia, Ann’s younger sister, who would be so deeply affected by the tragedy that she later took her own life.

In portraying Ann’s final day, Creagh shoots tight, and sticks to his subject like a limpet.

“The idea from the start was to stick with Ann,” he explains, “and move with her through the town. The camera might shift briefly on to people she met, go with them and come back to Ann, always to Ann. I felt we had to keep it really close, so that you’re really with them, and you feel what they’re doing, I wanted it to feel claustrophobic as well.

“When I was designing the film, I actually drew a map and I laid out the town so that I could get the full circle of where she was going. So when myself and the cinematographer Dave Grennan sat down, we very quickly worked out how we would shoot it. We really wanted to get that feeling of restless movement to it.”

The style of the film is pared back, suitably terse. “It’s 12-and-a-half minutes before the first word is uttered,” Creagh says.

“We shot in Boyle [Co Roscommon],” he tells me. “Obviously it would have been weird to shoot in Granard, insensitive in all sorts of ways. But even if we had wanted to, I wouldn’t have, because the town wouldn’t have worked for us logistically. I wanted this flow, the inside and the outside.

“My mother is from Sligo, so I spent a lot of my youth in Boyle and I know it very well, my brother has a house out there now, so I knew it inside out, and I knew it would work — there are certain streets in Boyle that haven’t changed since I was going there in the 1970s, which made it perfect for recreating the period.”

Zara Devlin, though, did visit Granard before shooting began. “Her and a friend went down to see it and get a feel of it. It’s a smallish town, the church is on the hill and the grotto is behind the church, and there’s something in it, something about it. You can feel it.”

Did he approach anybody in the Lovett family, friends or relations, before making the film?

“We had a contact in Granard, and they made inquiries, but nobody was interested. The parents are dead, obviously, and a lot of other people we portray in the film are too. We did get in contact with Ricky McDonnell a couple of years ago, and he said go ahead, but he wasn’t interested in being involved.”

In the aftermath of Ann’s death, the people of Granard kept their counsel, and the nuns who ran her school and others would claim they had no idea she was pregnant. Given that Ann went to full term before delivering her boy, whom she named Patrick, this seems unlikely.

“They must have known, I mean absolutely,” Creagh says. “[McDonnell] said he was walking down the street and he heard them talking about it, and he also said she had been very sick when she got pregnant first, in the first couple of months, so it would have been obvious enough that she was pregnant.”

Ann was shot on a budget of less than €200,000 in 12 days: RTÉ was a major backer. Somehow, Creagh, his cast and crew managed to turn this absurdly tight schedule to their advantage, lending their drama a compelling, visceral urgency.

Eileen Walsh is superb as Patricia Lovett, a deeply religious woman by all accounts who never leaves the house without her headscarf and seems paralysed by uncertainty, and fear of shame. From her perspective, what has happened to her daughter is so cataclysmic that perhaps it was easier to pretend it wasn’t happening at all.

This other Ireland portrayed in Ann seems hard to imagine at this remove. Creagh has grown children of his own: when they watch the film, I wonder, what do they make of it all? “It’s another planet to them,” he says, “because the younger generation know so much now, they’ve had so much access to information, so when they see the film, all they say is how could that happen? They can’t understand that at all.

“We did a little screening for the people of Boyle, for all the people who’d helped, from the guards, who were so helpful to us, to the priest who let us use the grounds.

"He didn’t want us to shoot there initially, and then we gave him the script and he said, yeah, you can do it. And at the screening, he was in the audience, and someone in the crowd said it’s terrible what the church did, and I said, actually no, it’s not just the church, it’s the church, the state, it’s the people, it’s the family, it’s everyone.

“We did another screening, at the Dublin Film Festival, and this man came up to me afterwards and he was crying, he couldn’t stop crying. He was a good friend of Ann’s, and his wife was with him, and she said to me you made her quite hard, you know, and that’s exactly how she was, you got her spot on.

“A lot of people contacted me about this film when I was making it, and there was one woman I spoke to who was a friend of Ann’s, and she told me all sorts of things, gave me a fuller sense of who she was, where she came from.”

And as he made the film, how did his opinion of Ann Lovett evolve and change? “To me she became such a strong woman, for 15 years of age. A strong, independent woman, who was so brave when you think about it, so brave.”

‘Ann’ is released in selected cinemas on Friday, April 28