Before they went back to the living room, Zelinski suggested that Rand take another dose of chilli.  Rand looked ill at the thought.  It occurred to Tam that raw chillies might be easier to swallow without tasting than a mouthful of Brand-X Tabasco sauce.  Rand was willing to try it.  Once.

“I’ll do you a favour and pop them into a glass of milk,” she said.  She swept up a few chillies from the pile on the kitchen counter.

“I’d recommend that you don’t,” Zelinski said apologetically.  Rand looked at him with dismay.  “Milk dilutes the effect of chillies,” said Zelinski, “so it’d be counter-productive.”

“Great,” said Rand.  “Pity you can’t get it in a patch.”

“Actually…” Zelinski paced the floor.  “You can.  I’m sure I’ve heard of it.  Capsaicin benefits people with arthritis.  It’s been produced as a prescription medicine.  Maybe I can find some for you.”

Strangely, Rand didn’t look happy at his little dream becoming a reality.  He shook his head and said, “Don’t make it a priority.”  Tam looked at him.  His eyes told her that he was embarrassed.  He wasn’t willing to remove Zelinski from the game board just to save burning his tongue.

But Zelinski had a bone and wasn’t letting it go.  “There’s something else,” he said.  “What if it’s available in a slow-release form, and we start taking it?” He pointed to himself and Tam.  “What if… it immunises us?”  There was a long moment of silence.  The scientific discovery of the week, if it was true.  “I’ve gotta make a phone call,” he said breathlessly.  He took out his phone and left the room.  Tam pushed some chopped chillies onto a dessert spoon and passed it to Rand.  He brushed half of them off, then took a deep breath.

At that moment Zelinski’s voice came in like a bullet. “He’s gone!”

The chilli hit the floor.  Tam and Rand ran into the living room.  Caleb was not on the couch.  He was not in the room.  Tam screamed his name.  How could all three of them have been so stupid?  They knew that he was prone to hallucinations, altered states and compulsive behaviour.  They ran three different directions.

Zelinski spotted him first.  He shouted something wild.  Tam and Rand thundered out.  Their footsteps on the hollow floor were like a stampede.  Zelinski was standing at the front door.

Tam crashed through.  Caleb was standing in his front yard.  He had his back to them and looked quite serene.  As they watched, he rubbed his forehead like an old man with Alzheimer’s, not sure where he was or what he had been doing.

Then he held his hands in front of him.  Zelinski said, “Shh,” pre-empting any sound Tam might make.  Tam stared.  Caleb felt the air.  It looked like dowsing, some medieval magic.  He rubbed his face, clearing his thoughts.  Used his hands again.  Testing what was in front of him.  They were like four geeks with one metal detector between them.

Then Caleb bent down.  He placed his hands on the grass.  He let out something like a hoarse laugh.  He looked off to the west.

“Fungus,” Zelinski whispered.  “Mycorrhizae.  I fucking knew it.”

A door opened.  Tam turned to see one of Caleb’s neighbours emerging from a house on the opposite corner.  Caleb heard it and stood up.  The spontaneous experiment was over.

The neighbour, a man who looked like a wizened actor, was juggling curiosity and anxiety as he came towards them.  At the same time, Caleb slowly approached him.  He nodded at some intuition only he could feel.

“Careful,” said Rand.  Meaning, stop Caleb before he does something weird.

Tamara had a tumbling sensation, like she just landed on this spot.  She got instant goosebumps and her eyes soaked up colour and light.  A massive adrenaline rush.

“That’s a Wreck,” she said.  The neighbour was already dead.  Coming out of his door so naturally was not what anyone expected.  He wasn’t wounded.  He didn’t look zombified.  Just a quiet man, living alone, curious.  But Caleb was drawn to him and now that she looked at his skin, it was an unhealthy plum colour.

“Shit, shit, shit,” said Rand.  He and Zelinski danced around on the spot and looked at the objects lying in Caleb’s yard.  A hosepipe.  A few orange boxes.  Two trash bins. A clutch of empty wine bottles.  Zelinski, very perceptively, pointed out their second obvious mistake of the day.  “Weapons,” he said.  “Why don’t we have any weapons?”

Tam’s mind threw up an image.  No time to explain.  She had to do it herself.  She ran to the spare bedroom, now converted into a gym.  She grabbed a weightlifting bar.