I shook my phone at him as if it were just-hunted prey and I was a wild dog. He opened his eyes for a little longer. ‘Are you talking to reporters?’

Caleb stood, clutching the soiled blanket to his skinny, white chest.

‘How could you be so stupid?’

He shrugged. ‘What are you talking about?’

I showed him the article. He barely glanced at it. ‘I haven’t talked to her. Not since last year.’

But something in me had opened. I couldn’t stop. ‘Why did you have to come home that day? What was so important about your sketchbook? If you’d stayed with Penelope, none of this would have happened!’

Caleb sneered. ‘Get out of my room, Mum. Please.’

In the sitting room, sickened by the article and my uncontrolled reaction to it, I collapsed onto the sofa and completed a familiar google search on Caleb’s name. Long blog posts, tweets and comment threads were devoted to vilifying him. Motives attributed to him spread like disease. People claimed he’d wanted to destroy the home he hated, or the schoolfriends who bullied him, or the town that rejected him. He was acting out some aspect of his dysfunctional family life, or against his over-protective, domineering mother.

Then, as on so many other occasions, I considered everyone from neighbours to students’ parents as potential murderers. I let my suspicions fall over Brunton like ashes. Everyone was a potential arsonist, from Rosie to the hardware shop guy. Even Jack. Some days, the tray of his ute was piled high with timber and wire for rebuilding fences. Other days, he’d be part of the clean-up team, helping move debris from the house sites of neighbours now living in a temporary caravan village on the oval. As CFA captain, he had never been more appreciated or needed than he was. Could the desire to be necessary be motivation enough?

In bed, I didn’t sleep. At school, I couldn’t concentrate. I was learning to live the awful pattern of a suspect’s life. My routine threatened to become as predictable as Caleb’s sullen silence.

But if fire had taught me anything, it was that nothing lasts. Three days later, I was on my way home from work when my handbag throbbed on the passenger seat. With its visible pulse, with all its possible meanings, that bag seemed a living thing. Its heart: my mobile phone. I spied a bus stop a few metres away and veered towards it. My bag came to life again before I had completely stopped. An insistent caller.

Foot firmly on the brake, I pulled my phone out. Its flashing screen announced Genevieve. In my chest, a vice tightened further. Genevieve rarely called. Something was wrong. Something new. I hit answer with my thumb.

‘You have to get home,’ Genevieve said. ‘Police are on their way. They have a search warrant.’