Jean Guy Beauvoir rolled the concept round in his clear, analytical mind. Was that somehow important? Was there a reason the murderer had chosen to kill CC de Poitiers by electric chair?

Was this retribution? Revenge? Was it punishment for some crime of CC’s? If so, it was the first such execution in Canada in fifty years.

‘What do you think?’ Gamache turned to the technician who’d asked the question, a young woman in overalls and a toolbelt. ‘And what’s your name?’

‘Céline Provost, sir. I’m an electrician with Sûreté technical services. I’m just here to wire up the computers.’

‘Bon, Agent Provost. What’s your theory?’

She stared at the diagram for a full minute, considering. ‘What was the voltage of the generator?’

Beauvoir told her. She nodded and thought some more. Then she shook her head.

‘I was wondering whether the murderer could have attached some more booster cables from the lamp to the chair, then buried the wires under the snow. That would electrify the chair.’

‘But?’

‘But it would mean the chair was live with electricity the whole time. As soon as the murderer attached the cables the chair would be electrified. Anyone touching it would get the charge. The murderer couldn’t guarantee Madame de Poitiers would be the first to touch it.’

‘There’d be no way to turn the current on and off?’

‘None, except from the truck generator and they make a lot of noise. Everyone would have noticed it going off. And if the murderer put the cables on at the last minute, that woman you said was sitting right there, well, she would have seen for sure.’

Gamache thought about it. She was right.

‘Sorry, sir.’

‘Other reports?’ Gamache asked as he sat back down.

For the next twenty minutes various agents reported on the crime scene findings, the preliminary analyses, the initial background checks.

‘So far,’ Agent Lacoste reported, ‘we know that Richard Lyon works as a glorified clerk in a clothing factory. He does their paperwork and makes out shift assignments. But in his spare time he’s invented this.’ She held up a diagram.

‘Enough mysteries,’ said Beauvoir. ‘What is it?’

‘Silent Velcro. Apparently the US military has a problem. Now that they’re doing more and more close quarters combat silence is crucial. They sneak up on their enemies.’ Lacoste crouched down at her desk and mimicked skulking around. ‘Then get ready to shoot. But they keep all their equipment attached to their uniforms by Velcro. As soon as the pocket is opened the Velcro rips off and their position is given away. It’s become a huge problem. Anyone who can invent silent Velcro will make a fortune.’

Gamache could see the wheels turning in everyone’s head.

‘And Lyon did?’ he asked.

‘Well, he invented this. It’s a system of keeping pockets shut using magnets.’

‘Ingenious,’ said Gamache.