Naden glowered at Poppy Mellor, who shrank a little further into the shadows.
‘What about it?’ he said.
‘We would have been able to identify all the members of the group from that photo anyway,’ said Cooper. ‘I suppose you guessed that. And you were right at the front, Mr Naden. As if you were conducting a guided walk. The others were looking to you. Nothing could disguise that.’
‘I told Sandra to delete that photo from her phone,’ said Naden grimly.
‘And she may have done. But she emailed it to herself first. She must have wanted a memento, I suppose. We found it on her laptop.’
‘Idiot woman. She was mad, you know.’
‘She is dead.’
‘Well, I didn’t kill her.’
‘No. But I know who you did kill, Mr Naden.’
Naden had moved closer without him noticing. He didn’t know which way to face now, which direction the threat might come from. The training manuals said you should make sure to have an escape route if you were likely to face a threat. But Cooper was aware only of the drop to the concrete beneath him, the low rail that wouldn’t stop anyone going over.
‘That night, when you were supposed to be at the bridge with the others,’ he said. ‘It didn’t all go wrong by accident, did it? You had a different plan from everyone else.’
He could sense Poppy stiffen and draw in a sharp breath.
‘You said it was the wrong day,’ said Cooper, ‘but your wife thought it was the right day. You knew who was actually wrong, didn’t you?’
With a smug smile, Naden leaned closer to stare into Cooper’s face. ‘She kept insisting it was the right day,’ he said. ‘She didn’t believe me, but kept on and on about it, even after we got home. That gave me the excuse to go out again later that evening, to check what was happening.’
‘But you went to meet George Redfearn instead.’
Naden nodded. ‘Well, he never suspected me. I looked too harmless, I suppose. But I’ve thought about it often enough over the years. Just not in relation to Redfearn.’
‘So how did you do it?’
‘I told him I knew his wife. I said I had some information to give him about her.’
‘Mrs Redfearn was in Paris at the time,’ said Cooper.
‘Exactly. One of her regular trips. She’s ten years younger than him, you know. He was bound to have a sneaking suspicion about what she was up to.’
‘But how did you know personal details about the Redfearns like that?’
Naden pursed his lips. ‘It’s general gossip.’
Cooper could tell Naden was lying.
‘Oh, I get it now,’ he said. ‘You employed Daniel Grady from Eden Valley Enquiries. He purported to be a property enquiry agent asking questions on behalf of a prospective house purchaser. His job is to pick up all the bits of gossip about the neighbours. I bet he’s very good at it, too. Even when money doesn’t change hands. He must be a godsend to potential blackmailers.’
Naden shrugged. ‘It doesn’t really matter, does it? I had the information I needed. And it worked. Redfearn came to meet me at Pilsbury Castle. It’s a very quiet spot, you know. No witnesses.’
‘Except there were,’ said Cooper.
‘Were there? That’s a shame.’
‘Some tourists staying at Pilsbury saw your car.’
Naden shrugged. ‘It hardly matters. As long as you realise Sally had nothing to do with it. I wouldn’t have involved her in something like that.’
‘How did you know she would keep insisting it was the right day?’
Now Naden laughed. ‘I take it you’re not married, Detective Sergeant?’
Cooper swallowed. ‘No, I’m not.’
‘It was obvious. Well, take it from me, when you’ve been married for a few years, some things become all too predictable. You don’t need to be able to read minds to work out what your partner will say. Sally has become very easy to predict.’
His tone of voice seemed to contradict the sense of his words. Cooper detected something deeper that Naden wasn’t saying, some aspect of his relationship that wasn’t on the surface.
‘But why do something so drastic?’ he said. ‘Why take the risk? It doesn’t make sense.’
‘Doesn’t it?’ Naden looked at the ground, as if contemplating the distance of the fall. ‘Sally is very sick, you know. She’s in a lot of pain most of the time.’
‘No, I didn’t know that.’
‘We’ve been together for so many years. It’s funny how nothing else seems to matter when you know someone’s going to die very soon. You consider all the things you’ve ever wanted to do, that you ought to do but have never dared to because of the risk to your liberty and reputation. And you start to think, Well, why not?’
Cooper nodded. That was something he could definitely understand. For months after Liz had been killed in the fire, he’d driven around the steepest roads in the Peak District late at night thinking, Well, why not?
‘I think that’s why Sally thinks about murder a lot too,’ said Naden. ‘She once told me that the best way to kill someone and get away with it is to lure them on to a high place and push them off. As long as there are no eyewitnesses, it’s impossible to prove forensically whether they were pushed or just fell.’
‘I’m not sure that’s true,’ said Cooper. ‘It depends on a lot of factors. For one thing, you’d need a good pretext to get someone into that position.’
Naden’s footsteps clanged on the metal walkway. The sound reverberated around the empty shed. And bounced off the hard concrete floor below.
‘Oh, it’s not that difficult,’ he said.
Diane Fry and Luke Irvine entered the factory through the same door Cooper had used. Outside in Hartington, the last few fireworks were spluttering to a halt after a spectacular finale.
Fry kicked against a pair of wellington boots standing by a doorway and crunched through a pile of dusty leaflets on the floor.
‘What a mess,’ said Irvine in a hushed tone.
‘Let’s hope we find nothing worse,’ said Fry.
They moved steadily through the rooms and were joined by two uniformed officers. The beams of their torches illuminated the darkest corners, alighting on old filing cabinets and mysterious heaps of abandoned equipment.
‘Ben?’ Fry called.
She moved ahead, passing through a doorway, then another, following some instinct she couldn’t explain. She knew Cooper was here, because his car was parked nearby. But she didn’t know who else was.
Ben Cooper hardly knew what happened next. He and Geoff Naden were staring into each other’s eyes. He was aware of Naden’s left hand reaching out to grasp his shoulder, and Naden’s right hand coming up with a length of steel pipe he must have picked up from the floor.
Cooper instinctively grabbed his wrist. He wasn’t as heavy as Naden. He could feel the difference as soon as they made physical contact. He didn’t want either of them to go over that rail. But he was also conscious of Poppy Mellor immediately behind him. Cooper needed to turn round to see what she was doing, but he was reluctant to take his eyes off the other man. He felt for his extendable baton, concealed in a pocket of his coat.
‘Be sensible, Mr Naden,’ he said. ‘This won’t help anyone. It will only make things worse for you.’
‘It doesn’t matter to me any more,’ said Naden grimly.
And then there was a chaos of people shouting and lights swinging across the ceiling, picking up the figures on the walkway, then passing on and reflecting off the skylights, flashing like the starbursts in the sky over Hartington. Cooper heard his own name called, boots clanging on the metal steps.
In an explosion of light he saw Naden raising the length of pipe. Then an impact from behind threw him off balance and he dropped his baton as he threw out a hand to clutch at the rail and save himself from falling.
He dropped to his knees with the breath knocked out of him, expecting a blow to fall at any second. He heard Naden cry out — one loud, angry yell that turned into a scream of fear. Then a sickening impact thudded through the empty shed.