He had three hours until lights-out. It would be touch and go. He stacked all the items on his top shelf, neatly, and roughly in the order in which he’d require them. He grabbed the BIC razors, the toothbrushes and the dental floss first, and moved them to his desk.

Ten minutes later, Jax was holding a precision cutting tool. Having removed the bristles from one of the three toothbrushes with a razor, he had used the same blade to make a deep groove in the plastic head. He’d then slid a fresh razor in the slot, before fastening it with tightly wound floss.

He took the Coke cans, the tuna and the chips from the shelf next. He felt both a little queasy and a little high after sculling both cans and speed-eating the chips, the caffeine, sugar and fat combining to deliver a sickly hit. He told himself he should have ordered Coke Zero and veggie chips from the Healthier Options page. Too late now.

He dumped the entire contents of the can of tuna into his bin. The stench didn’t help his stomach, his room immediately smelling like a deep-sea fishing boat, and the stink would be unbearable in a few days. But he wasn’t planning on being around for that.

Jax used his toothbrush blade to cut the empty Coke cans in half. He threw the top halves of the cans into the bin before heading to his sink, where he thoroughly washed the bottom halves, the tuna tin and the chip packet with warm water and soap before towelling them dry.

Next, Jax took the Isocol and the four bottles of Easy-Off Bam from his shelf and placed them alongside the cleaned and dried cans, tin and packet. He squirted a healthy serving of Isocol into the bottom of the tuna can, retrieved the lighter he’d stolen from one of the methadone gang earlier that day when he’d been out of it, and set the gel alight. The Isocol burned hot and bright, being pure ethanol, with a peak burning temperature of 1920 degrees Celsius. There was no way Jax’s Isocol fire was that hot – it didn’t have enough oxygen – but it was hot enough to extract hydrogen peroxide from his bleach.

Jax used his cutting tool to make a hole just below the top edge of one of his cans. He then grabbed another toothbrush from the three-pack and stuck the brushless end into the hole to make a handle. He filled the half-can up to the handle hole with Easy-Off Bam and held the can over the flame until all the liquid had evaporated. Then he took the last toothbrush from the packet and used it to sweep up the fine white powder left at the bottom of the can – pure hydrogen peroxide – into the chip packet.