In the end it was all too easy. Using Mulhearn's phone I sent a text to Claire telling her that her husband had been picked up by the law. She would have found out shortly anyway – as soon as Wheelan's solicitor had been briefed. Almost immediately she sent a return text. A brief smile crossed my lips.

It's easier now than it used to be in the old days. I don't have to speak to people unless I want as most people on a mobile phone contract get given five thousand free texts. Unless you're a teenage girl, like Alexa with a wide circle of friends, most people never use them. However, nobody likes to think that they are wasting their free texts so they use them whenever possible.

I checked Claire's text. She would be waiting for me at home. I engaged first and drove the long way round, over the Holdingham roundabout and then down through the congested centre of Sleaford onto Boston Road and then looped up Old Place. As soon as my Cherokee pulled into the driveway, Claire came running out of the door, clutching her handbag. She wrenched open the passenger side door and only then pulled up in confusion.

"Hennessy? What are you doing here?" Claire asked.

"Mulhearn's busy dealing with the arrests. As I'm sure you can appreciate. As I was in the area he asked me to take you down the cop shop instead." I smiled and tried to look friendly.

This was the tricky part. If Claire Wheelan smelled a rat, then I would have to use force. I didn't want that. But soft living and worry for her new husband had weakened her sense of danger and Claire got in beside me, her handbag on her lap.

"I didn't know you were working for my husband now," said Claire. "He never told me."

I edged out into the traffic. "I didn't want it spread all over, but McTeague's yesterday's man. So I switched sides," I lied.

Claire nodded. People in my line of business usually have as much loyalty to their boss as an overpaid Premier League club footballer has to their team. That is: zero. As soon as a better deal comes along they're off even if the ink is barely dry on their old contract. She should have known better. Because I'm like one of those old fashioned one-club players you sometimes still get.

"Mulhearn said Wheelan needs something picking up from his tanning studio. We'll swing by there on our way to the cop shop. Okay?"

I parked outside the Beauticians. It had been renovated since my fire-bombing raid and everything was brand new with a luxurious purple and black interior. The place was closed and the towels were piled up in neat fluffy heaps. Not surprising the place wasn't open. Earlier, using Mulhearn's phone I had sent texts to all the staff telling them not to come in today. Unlocking the salon, I showed Claire inside.

"It's a USB memory stick hidden in the sun-bed room. It holds some documents Wheelan will need for his defence. Give us a hand to look for it, please," I said. Claire was way too trusting. She followed me into one of the sun-bed rooms. Claire peered around with a puzzled look on her face. There weren't many places you could hide even something as small as a memory stick. She turned to me just as I took a fresh bottle of chloroform out of my jacket pocket that I'd sourced from Dr. Nabi-Khan.

"Hennessy? What are...?" was all Claire said before I clamped a hand towel over her face and poured out a dose of the Halothane. The fumes filled the air, masking the smell of tanning lotion. Claire struggled frantically and her manicured nail scratched my hand drawing blood. Slowly, slowly, her struggles diminished and her limbs stilled.

However, before Claire went under completely, I took away the rag. She looked up at me. It's funny but I'd never before noticed how pretty Claire's eyes were – a sort of turquoise blue. I half led, half dragged her over to a chair and sat her down.

"McTeague sent me to give you a warning," I told her. "Remember, he can reach out and take you whenever he wants."

Claire nodded but I'm not sure if she was capable of taking it in. "Let me fetch you a glass of water." Leaving the sun bed room I crossed to the small back kitchen for the staff's use and fetched a bottle of water from the fridge before returning to Claire. She still looked groggy and ill. From my jacket pocket I took out a couple of pills that my friend, Dr. Pervert, had also given me.

"These will help you recover faster," I lied, holding them out. Claire shook her head weakly but I put them in her mouth and then held the bottle of water to her lips giving her no chance to spit them out or refuse. She jerked her head around but I tapped her throat, forcing her to swallow.

"Feel better?" I asked.

Terror filled Claire's eyes and they opened wide. She knew I wasn't there to help her, especially when I placed the stinking rag back over her face. I dripped a few more drops of Halothane onto the cloth. Claire could no longer struggle as much as earlier and within minutes she was as limp as a rag doll. I gently let her slide down onto the tiled floor.

I looked down at Claire for a minute as she breathed. I felt no sympathy for her. If she hadn't taken up with Wheelan none of this gang war would have taken place. McTeague would have kept on quietly running the East Midlands with Wheelan as one of his lieutenants. But Wheelan had wanted it all and now he was going to lose it all.

Kneeling by Claire, I stripped her naked and then lifted her up and placed her on the sun-bed. She looked like she was sleeping. I lowered the coffin-like lid, put in the tokens and turned the dial to the max – a full hour's worth of high tan. As I waited, I folded her clothes neatly, wiped down all the surfaces I'd touched and then brought in a couple of magazines from reception. I wondered about popping out to Mulhearn's Jeep for my Telegraph but that would have been an unnecessary risk.

Claire stirred and muttered thickly until I gave her another dose of chloroform. At this point, hepatotoxicity was the least of her worries. The rest of the hour passed slowly. And so did the second after I turned Claire over onto her back, fed the slot with more tokens and then gave her front an hour's full tan.

Finally, at long last, the sun-bed's dial turned full circle until it reached the off position. I stood. Big fluid filled blisters were already forming on her breasts, stomach, thighs and upper arms. There would be many more later. I dreaded to think what her back and buttocks were like.

Claire was a dead woman. Not now but within a few days we would be attending her funeral. The pills I'd forced down her were psoralen, which greatly enhances the effects of light therapy. In medicine, they are mostly used for the treatment of skin conditions such as psoriasis before a patient goes under the lamp. However, in Claire's case they would give her phototoxicity. Together with the overdose of UV rays from the sun-bed, she was well on the way to getting massive third degree burns leading to sepsis – blood poisoning. This is what Dr. Nabi-Khan explained to me when I'd visited him a few days before.

And the great thing was that no-one would suspect a thing. Everyone knew that Claire was a high-maintenance kind of girl addicted to the sun beds and beauty parlours. What could be more natural that she would take a short cut by using black market psoralen sourced from some dodgy website and then fall asleep on the sun-bed? Because it was such a rare cause of death, I already knew the coroner's verdict: Accidental Death. That would do me and McTeague fine.

Collecting my gear and making sure I didn't touch anything else, I let myself out of the Beauticians salon. The sun had broken through the clouds and it promised to be a beautiful day. On a bench over the road three youths sat passing a bottle of White Lightning cider between them whilst a girl tried to cadge a smoke from them. Their BMX bikes were propped up against an abandoned retail unit. Welcome to Sleazeford, I thought, recognising two of the yobs as the lads who had keyed my Audi coupé months before.

As I crossed the road towards them, my BlackBerry rang. Wondering who was calling me, I looked at the display. It was my husband. Smiling, I took the call.

"I've been trying to reach you all morning, honey. How was the conference?" he asked.

"Great. My presentation went well and the chairman's only just finished wrapping the whole thing up. Listen, I'll pick up a nice bottle of Aussie Shiraz on the way home and prepare a beef casserole for dinner," I told him. He knows nothing of what I really do.

He thanked me. My husband's a good man. Unlike me – I'm a bad woman to know. As those youths were about to find out.