An American boy who was made to threaten President Donald Trump in an Islamic State group video says it was "sweet relief" to return to the US.
Matthew, taken to Syria by his mother and stepfather, was 10 when he was filmed telling Mr Trump to prepare for a battle on US soil.
Now 13, he has been living with his father for a year, after being flown home by the US military in 2018.
"It's happened and it's done. It's all behind me now," he told the BBC.
"I was so young I did not really understand any of it."
Matthew has had counselling to help him deal with everything that happened to him and is coping well.
His stepfather, Moussa Elhassani, died in a suspected drone attack in the summer of 2017, while his mother, Samantha Sally, was convicted earlier this month of financing terrorism and sentenced to six-and-a-half years in prison.
It was in April 2015 when the seemingly ordinary American family crossed into IS territory from the Turkish border province of Sanliurfa.
"We ran across an area that was very dark. It was at night, there was a lot of random spots of barbed wire… There wasn't much going through my head except, 'I need to run,'" Matthew said, speaking about his ordeal for the first time to the BBC's Panorama programme and to Frontline, a programme made by US public broadcaster PBS.
In the city IS claimed as its capital, Raqqa, Matthew's stepfather, Elhassani, was sent for military training and became an IS sniper.
Then eight years old, Matthew did his best to make sense of his new home. "When we were first in Raqqa, we were in the city parts. It was pretty noisy, gunshots normally," he said. "Once in a while a random explosion, like far away, though. So we didn't have too much to worry about."
But in early 2017 his mother emailed her sister in the US with a desperate plea for money to help the family escape, attaching extremely disturbing videos of Matthew.
In one, Elhassani forced Matthew to assemble a suicide belt. At his stepfather's instruction, Matthew role-played how he would welcome potential American rescuers, but then kill them by detonating the explosives.
In another video, he was seen taking apart a loaded AK-47, challenged by his stepfather to do so in under a minute.
As the US-led coalition intensified its airstrikes on Raqqa, a bomb hit a neighbouring house, which collapsed on to the family home, leaving Matthew to feel his way out through the rubble and dust.
By August 2017, Raqqa was in ruins, but the Islamic State group was still predicting victory and it forced Matthew to deliver a message of defiance. It released a video of him, then aged 10, threatening the president of the United States.
"My message to Trump, the puppet of the Jews: Allah has promised us victory and he's promised you defeat," said Matthew, reciting lines he had been made to learn. "This battle is not going to end in Raqqa or Mosul. It's going to end in your lands… So get ready, for the fighting has just begun."
In his interview, Matthew said he was given no choice but to take part in the video, because of his stepfather's outbursts of anger. "He was starting to lose it, like he was mentally unstable, very mentally unstable," he said.
Shortly afterwards, Elhassani was killed in a suspected drone strike. "I was happy 'cause I didn't like him, obviously," Matthew said. "I don't think I should have been, because a person died, but I was. We were all crying out of joy."
Matthew's mother, Samantha Sally, was then able to pay people smugglers to get herself and her four children out of IS territory, with Matthew hidden inside a barrel on the back of a truck as it passed through IS checkpoints.
When they reached Kurdish-controlled territory, they were held in a detention camp, and it's there in the winter of 2017 that Panorama first started talking to Sally.
She said she had been tricked by her husband into taking her family to Syria and that she had had no idea what he had been planning.
Once in Raqqa, he had become violent towards her, she said. She admitted that they had bought two Yazidi teenage girls as slaves, and that her husband had regularly raped them.
She continued to stick to the story that she had been tricked after the family's return to the US, while she was in jail awaiting trial. Although she had supported her husband "in his stupid ventures", she was not guilty of supporting him to join IS, she insisted.
But the Panorama/Frontline investigation uncovered evidence that undermined this story.
A member of the Elhassani family said that Moussa had become obsessed with IS in the months before the family left the US, and that he had seen him watching IS propaganda, including videos of executions, in the family home.
A friend of Samantha Sally's also recalled a conversation with her in which she had said her husband had told her he'd been called to join "the holy war".
And the Panorama/Frontline investigation discovered that Sally had made a series of trips to Hong Kong in the weeks before the family left the US, depositing at least $30,000 in cash and gold in safety deposit boxes.
After almost 12 months behind bars, Sally changed her story and pleaded guilty to financing terrorism as part of a plea deal. Struggling to accept her guilt, she said, "It was the only deal they could have offered with the T-word that didn't put the guidelines at a lifetime sentence."
Prosecutors described as "horrifying" their discovery that Sally had helped film the videos of her son Matthew being forced to assemble a suicide belt and take apart an AK-47.
They said it may never be known why she had helped her husband to join IS. Her defence argued that she had been coerced by her controlling husband.
Speaking about how it felt to step back on to US soil, Matthew said: "It's like being in tight clothes or tight socks and shoes all day and then just taking it off and just feeling nice and chilling in a hot bath. That's what it felt like. Like sweet relief. It felt good."
Viewers in the UK can watch Return from ISIS: A Family's Story on Panorama, at 21:00 on BBC One on 23 November, or catch up later online.
The first episode of I'm Not a Monster, a 10-part podcast telling the family's story, will be available for download on Monday.