So she plucked the joint from Mel’s fingers and put the damp roach-end between her lips and took a large puff. But she didn’t draw the smoke down into her lungs, holding it instead in her mouth and throat, blowing it out a few moments later.

It would have been both easy and fun to participate a little more wholeheartedly. But it was never a good idea to get strung out on drugs while undercover. If you were strung out, you could make mistakes, screw up an operation or even make an error that could turn out to be fatal to you or someone else.

‘Want to see something funny?’ said Seema.

Bailey shrugged and nodded.

Seema turned to Mel. ‘Hey, Mel, did you know that the universe goes on forever?’

Mel’s face slowly screwed up into a painful frown as she attempted to comprehend the fact. For a while, her eyes were stuck in an odd squint.

‘That does my head in,’ she said. ‘Why would you say something like that?’

Seema and Kay collapsed into paroxysms of laughter.

‘Aren’t you worried the screws might come in here and catch us?’ said Bailey. ‘I mean, it’s not exactly subtle… the smell and everything.’

They looked at each other and shrugged indifferently.

‘You know what,’ said Kay, ‘I think the authorities turn a blind eye on us smoking weed because it makes us behave. You don’t see us committing crimes or starting riots. We’re just sitting here and chilling out, not causing trouble to anybody.’

She tossed the bag of weed to Mel.

‘Roll us a joint, Mel.’

Mel picked up a pack of rolling papers and plucked out several sheets. Her long brown fingers manipulated the papers with a fluid dexterity as she fashioned the foundations of a large joint, her tongue darting out to lick the gummed strips to glue them together.

‘She’s the best joint roller in here,’ said Seema. ‘Papercraft is her forte. Hence all the origami animals.’

Bailey watched her skin up, silently impressed by her casual expertise. Here was a master at work, one whose vacant demeanour belied a genuine aptitude for the task at hand.

After she’d finished packing the dope in, Mel rolled it smoothly into a long tight cone, gracefully twisting the loose paper at the end into a neat point which sealed the joint. She tore a piece of cardboard off the pack of rolling papers and rolled it into a roach, which she inserted into the other end. She held the joint up for them to see.

‘Nine and three-quarters,’ said Seema.

Mel smiled proudly.

‘I still think mine was an eight,’ muttered Kay.

The first joint came round to Bailey again. There were now two joints circulating and the air was denser than ever with smoke. The poor ventilation in the cells, courtesy of the prison’s outmoded design, didn’t help the situation.

Despite attempting not to inhale directly from the joints, she couldn’t help but passively smoke what was fairly potent marijuana, and she was starting to feel quite stoned. She had that distinct fuzziness at the edges of her consciousness, accompanied by a noticeable disruption to her linear thinking patterns. It was quite pleasant, she couldn’t deny it.