It feels surreal to be overhearing pleasantries between some of crime’s most unpleasant characters. I’m free to chat to them in the prison kitchen, where they prepare meals with long knives, and in the gym, where they throw around heavy weights on metal barbells.
We talk about life in HMP Frankland and HMP Full Sutton – two of the country’s most high security prisons. One inmate I speak to has been in for 21 years, another 18. We discuss the food, the cells and their hopes for the future. All are painstakingly polite.
I fall foul of a prison taboo by asking them what they’re all in for.
"I’d rather not say," they each repeat. I step away and ask the prison governor instead: murder; child rape; terrorism.
It is the latter category of criminal we are primarily here to film.
Mixed in with the likes of the Soham murderer Ian Huntley and Millie Dowler’s killer Levi Bellfield are terrorists who’ve plotted or successfully executed some of the worst atrocities ever committed on British soil.
The Ministry of Justice has given us unprecedented access to both prisons to see how they attempt to reform some of the most hardened minds.
It follows criticism of the way several terrorists have been released from jail only to reoffend – most notably Usman Khan, who claimed to have been deradicalised, before murdering Saskia Jones and Jack Merritt in the Fishmonger’s Hall attack in 2019.
He had been on the same deradicalisation programmes that all terrorists we meet are being offered inside the prisons.
Primarily, the schemes involve one-to-one mentoring and psychological work to try and understand why the offenders were drawn into terrorism and what might help them to leave it behind.
The prison imams also approach them to offer religious guidance.
Most terrorists follow Islamist ideology, but a growing group – around a quarter – take their inspiration from the far right.
The vast majority of offenders are housed on the same wings as other prisoners.
We pass several in the lunch queue. The most violent are sent to a close surveillance centre - and then there are those who pose an even graver danger.
For the first time ever we were invited to film inside the Separation Centre at HMP Frankland.
Essentially a "prison inside a prison," this wing is reserved for the most radical terrorists, who are kept away from the general prison population to prevent them from recruiting others.
In the yard we saw their exercise regime and in the communal areas we read their laundry roster.
Just five inmates are kept on the wing, free to socialise with one another. The prison officers tell me they sometimes play scrabble with the inmates and chat about the football.
Standing right outside the cell doors, I can hear the prisoners shouting to one another through open windows.
I’m fairly sure they know I’m there, as they chat about everything from what’s on the radio to when they’ll be taking their naps.
The prisoners in the Separation Centre at HMP Frankland shout to each other through open windows
And I am just arms length from the most dangerous mind of all.
We’ve learnt that Hashem Abedi – the brother of the Manchester Arena bomber, who helped plot the attack – is inside this centre.
There is one inmate in particular who we notice Abedi associating with.
In the prison control room, we watch on CCTV as a man we believe to be Abedi takes a walk around the yard with another offender we’ve identified as a former Taliban fighter, who’s also been jailed for terrorism offences.
Only one of the five prisoners on the wing is actively engaging in any attempt to deradicalise. And we’ve learnt that it’s not Abedi.
We understand he is refusing to take part in the programmes, as debate continues over whether the separation centre simply hardens the most stubborn minds.
Some of the inmates refuse to even talk to staff or engage with any of the prison regime.
One staff member we spoke to, who prepares the inmates for eventual release, admits that for some terrorists, prison is simply a “holding centre”, with no realistic prospect of deradicalisation.
'There are some people that are so entrenched in their views... that we just become a holding centre for them', says Richard Vipond, Probation Officer and Prison Offender Manager at HMP Frankland'
Abedi will be held for a minimum of 55 years.
Whether he spends them all in the separation centre, or out on the general wing with murderers and paedophiles, will partly depend on his own appetite for reform.