Behind prison bars, there's a strange ecosystem among inmates that involves bartering household goods, drug deals, and surprising debt spirals that can be hard to escape. Author Carl Cattermole explains.

The following is an extract from Prison: A Survival Guide by Carl Cattermole, out now through Ebury Press.

It’s not hard to see why people have their little side hustles in Her Majesty’s Prisons, the UK jail system. When legitimate economies are made impossible, people become black marketeers, that’s just how it goes. Tobacco used to be the unit of currency until it was banned very recently and so, wistfully, I tell you that gone are the days of ‘Barons’ sitting there with stacks of Golden Virginia like it was gold bullion. The nouveau Barons stack tins of fish and toiletries so high you can’t see out the cell window.

It’s a bit like living in Asterix & Obelix’s village – everyone has their own little enterprise. Kitchen workers will smuggle you some black pepper or herbs in exchange for a tin or two of tuna. The laundry and stores lot will make sure your clothes actually get clean in return for an energy drink.

I’d advise buying clippers and becoming a wing barber but be warned: you might get into tuna-based territorial conflict (no joke)

The guy in charge of kit-change will make sure you get bed sheets that aren’t totally covered in pubes if you give him some instant noodles. Hairdressers make a killing (a killing of tuna and shower gel) because everyone wants to look prim with a fresh trim for their visit – I’d advise buying clippers and becoming a wing barber but be warned: you might get into tuna-based territorial conflict (no joke).

Then there are medium-value items. The local artiste will draw you a birthday card, a love letter or a get well soon card. The craftsmen will build you a set of drawers from matchsticks and glue. Hooch costs around £10 per litre depending on the quality.

Expensive bits like drugs, tobacco (50g currently costs around £500!) or buying a stereo off someone will be paid for beyond the prison walls. The buyer’s friend on The Out (outside) will pay the seller’s friend on The Out and once payment is received, the item will be handed over.

In fact, some people come to prison just to make money or pay off debts. They’ll swallow as many drugs as possible then intentionally get arrested in order to sell the drugs on the wing. This lifestyle is more bizarre the more you think about it: no one does this unless they truly need to (or are forced to).

Debt

On The Out there are payday loan shops, bookies, and banks, and the prison equivalent are the Barons, who lend money using a scheme known as Double Bubble. It’s as it sounds – you borrow something (drugs/nicotine patches/painkillers/food/toiletries) then repay double the next week. If you can’t manage the payback, you might enter a debt spiral where you are forced to pay back more and more and more.

The induction wing (where new prisoners arrive) is the hotspot for this stuff because this is where people are at their most strung out, their least well–provisioned (waiting a week or two for their first canteen, and that’s if they have money) and their most innocent.

They’ll swallow as many drugs as possible then intentionally get arrested in order to sell the drugs on the wing

I mean, a lot of people borrow and do manage to pay it back, but if you can’t you’ll end up in a bad way. Beaten up, fingers slammed in a cell door, or you might become a Joey.

In extreme cases people get themselves put on cucumbers (or numbers, the Vulnerable Persons Unit) or try to move prisons, but Barons aren’t stupid: debtors are required to give family details and families are targeted if the debtor gets out of reach.

Whilst High Street money businesses legally use bailiff thugs in uniform, Barons do the same with boys in trackies: truth be told, the difference isn’t that big.

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