Kate wants this man badly – just not for the reason he thinks...

"You look amazing," says Tina, hands on her hips in skimpy leather hot pants that barely skim her butt cheeks. Only Tina could pull off something that TOWIE and still look classy.

I check myself out in the mirror, but the girl staring back at me in an embellished bodycon dress with smoky eyes and a massive blow-dry looks like a complete stranger. I never usually wear make up, this isn't my face and it's definitely not an outfit I'd pick out for myself. But that's the desired effect, I don't want to be Kate tonight. I want to step into somebody else's shoes.

We polish off two glasses of cava "for good luck" as Tina puts it, but we both know that it's really Dutch courage. Our car's ready and waiting outside which is lucky cause we're both underdressed for the late October chill.

There's a huge queue in front of the club but Tina tells the driver to pull up right by the entrance. As we step out of the car, an overbuilt bouncer unclips the rope to let us straight through with a wink. That's a good start, despite the fact that he gives me the creeps.

Tina orders us a couple of Jaeger bombs and flirts with a gorgeous, Brazilian barman. I'm too distracted to concentrate on what they're saying. My stomach's doing acrobatics as I scan the floor looking for him. A sharp elbow jabs into my waist. "There's your man," says Tina. "Three o'clock."

He's even better looking than I remembered. All chiseled jaw and carefully trimmed five o'clock shadow. He's picked up a healthy tan from his latest trip to LA and his muscles are rippling out of his rolled up sleeves. You're quite a looker Marc Burgess, I think.

"Come on, let's dance," says Tina, pulling me over to a miniscule space directly in front of his line of vision. We start writhing to the house music, not my cup of tea but then again, if I had it my way I'd be curled up on the sofa with an actual cup of tea watching X Factor right now, not in Mechu, a fancy club in Birmingham, in six inch heals that are already killing my feet.

We make a good show of being the pissed party girls and dance with a few of the guys that have circled around us. Tina looks like she's really enjoying herself but I have no patience for it, I keep steeling looks at him. Before long I feel his eyes on me and yes, a flicker of victory does spark up inside. One of his friends makes a beeline towards us and Tina quickly has him entranced, skinny arms wrapped around his neck. I want to get this done with and approach him first but we've been over this, it's important that he comes to me. You can tell that he's the sort of man who likes to get what he wants.

Tina winds herself around his mate and I'm dancing on my own for a minute when I feel a hand on my waist. I don't even have to look round to know that it's him and I surprise myself by feeling a surge of electricity crackle from the spot where he's touching me lightly.

"You're a great dancer," he says in gruff tones. "Champagne?"

I bat my lashes and pretend to hesitate. "Only if my friend can join us," I reply, glancing back at Tina.

"Of course," he says. "The more the merrier. Dan, come and have a drink, bring your lovely friend."

He takes my hand and walks me up the three steps to his booth where an ice bucket and a bottle of Laurent Perrier await. Three girls are already plastered across a couple of men on the velvet sofas, but they instinctively make space for Marc.

He pours out some glasses toasting, "The most beautiful women in the room." Inwardly I'm rolling my eyes, but I do my best to giggle and pretend to blush.

"Marc Burgess," he says offering me his hand. "What's your name?"

"Annabelle, but my friends call me Belle," I reply. Because I'm not Kate Jackson tonight. Tonight, I'm Annabelle Hunt, and I'm here to put this man behind bars.

Tonight, I'm Annabelle Hunt, and I'm here to put this man behind bars.

***

"My god he is so into you," says Tina from the toilet cubicle. "You've been talking for hours."

I reapply my lipstick and wait for a group of girls to stagger out.

"I can't get him to dance," I say, sampling the hand cream and avoiding her eye as she stares me out in the mirror. "He says he never dances. What's he doing spending four nights a week in this place if he doesn't dance?"

"Picking up hot girls like you!" she replies. "I don't mind my one, he's as thick as shit but I think he's quite cute. So... what's Marc like?" She whips me on the arm with one of the crisp, white hand towels. "Do you feel comfortable going through with this?"

The truth is that I'm more than happy to keep flirting; I'm incredibly attracted to him. It's not just that he's gorgeous, with his intense green eyes and his ripped body, but every time he touches me I feel a surge of desire. I shouldn't have accepted this job when I've not had sex for six months. I think back to the last time with my ex and it comes as no surprise that it wasn't particularly memorable.

"He's alright; he's actually quite intelligent," I reply.

"Kate, he's wanted for money laundering and five counts of fraud. They've taken him in seven times and still can't pin anything on him. We wouldn't be here if he wasn't intelligent."

"I know, I know, I meant interesting. I didn't expect him to be so interesting."

"Oh my god you're into him!"

A couple of girls walk in giggling and we both put our imaginary masks back on.

"Can't say I blame you Belle, he's a looker."

I'm not into him Ashley," I snarl.

"Yeah, yeah, come on, I want to dance," she says, pushing me out of the door, then muttering under her breath. "Look, if you get something out of it, it's all the same to me, as long as we get the job done."

Kate pulls his friend back to the dancefloor and I sit down next to Marc. He's talking to me intently about the house that he's designed; he's clearly passionate about architecture. It's going straight over my head because all I can think about is the feel of his leg resting against mine and his hand that keeps briefly stroking my arm, sending tingling sensations straight through me.

"That sounds incredible, you're lucky to have such a unique home." I'm searching for something to say to hide the fact that I've been tracing the line of defined muscles in his arms.

"Come and see it. Seriously, I want to show you, let's go now," he says. It's what I was hoping for, it's the reason we're here, but it's not what I expected. I thought he'd be sleazy and I'd play the part of ditsy bimbo, but he's enigmatic, excited even.

"I don't know... I'll ask Ashley." Don't act too keen, let him think it's his idea. He'll never suspect.

"Do you not go anywhere without your friend? Listen, she looks like she's having a good time as she is. If you're not interested, don't worry, it was just an idea," he says.

I pretend to hesitate before saying, "Let me go and talk to her, make sure she's alright on her own." Tina can handle herself but this wasn't part of the plan.

I pull her away from Marc's friend over to the steps by his booth.

"Suggest that we go outside," I say, my hand cupped over her ear.

"WHAT?" she shouts over the music "I CAN'T HEAR YOU, LET'S GO OUTSIDE FOR A FAG."

I glance back at Marc with a look that says 'joining us'?

"I don't smoke," he calls back.

The original plan was for us both to go back for one of his famous after-parties, fool around in the pool with him and his mates and seize the opportunity to plant some cameras, but he's not what I expected, and part of me suspects that being alone with Marc Burgess won't be such a chore after all.

"If you're sure you want to do this," says Tina, "You know where we are."

Tina makes a good show of being eager to return to the dancefloor and I accept Marc's invitation. His driver is waiting outside and I pretend to be impressed with the extravagance when, in reality, I've been watching his routine for months and my own driver, a fully qualified police officer, is just around the next corner.

In the back of the car, Marc's more subdued. He tucks my hair behind my ear and leans in to kiss me on the neck. An incredible shiver breaks out across my back.

We pull up outside the glass fronted house that I've seen photos of a hundred times in our files, and I pretend to be shocked by the impressive aquarium wall that we've already glimpsed from the CCTV footage.

I start to ask him about it but he's stopped chatting, distracted now. I realize with delight that he's staring intently at me, his eyes lingering on my waist, my legs, my chest. He runs his thumb gently along the side of my dress, tracing the curve of my body before guiding me down the spiral staircase into his bedroom. A minimalistic iron bed stands alone in the middle of a sparse white room. There's a screen across one wall that's the size of a small cinema. So this is where all of your stolen money goes, I think.

I let out a sigh that's completely genuine as he pushes me back onto the bed and I notice four wide, black silk ribbons are tied to the bed frame.

He kisses me so urgently, gripping my thighs in his hands, pressing into me with his body that, for a second, I forget the plan. Every bit of him is hard and strong. I'd happily rip his clothes off there and then but he stops, reaches up to get one of the ribbons and ties my wrists together. Oh god. Talk about a wake up call. Have I let this go way too far?

"What are your fantasies?" he whispers, "I want to know your secrets."

"This," I gasp back at him, despite myself. "I like this."

He ties my hands to the bedstead and I'm fully aware that he's strong enough to do this without my consent. Then again, I could break out of these ribbons without a second thought, and besides, I'm completely compliant, biting down on my lip and staring intently back at him. He runs his hands down to my breasts to feel hardened nipples pushing up through my dress. He reaches under me to unzip it, staring at me the whole while before pulling it down over my legs. I'm not wearing a bra and my boobs are pert, waiting for his touch, but he just stares as he pulls my lace knickers off after the dress. He starts to tie my feet up and I lie there, naked, exposed, with him fully dressed, loving every second.

He takes off his shirt and I feel another wave of desire as I stare at his tanned, muscular chest, hard above his bulging jeans. I know this is wrong, but there's no way out. And honestly? I don't want one.

He leans down and kisses me, his lightly stubbled cheek brushing against me as he licks my left nipple. He takes the right nipple in his hand and rubs it under his thumb as he bites down gently, teasingly.

I'm groaning with desire when he slips more fingers inside of me. I gasp, it's intense, forceful. I feel myself opening up to welcome him in and lose all sense of time as he reaches inside, stroking my clit with his thumb. When I climax with a small cry, he takes his hand away and starts to kiss me, from the inside of my legs, right down to my feet.

He runs his hands down to my breasts to feel hardened nipples pushing up through my dress

The sight of him fighting to restrain himself, still dressed from the chest down while I'm naked, ready and waiting, is a massive turn on. He works his way back up my legs with his mouth. His tongue flickers inside me, stroking and kissing and licking while his hands grip my legs and I writhe underneath him, gasping in pleasure.

I can't tell how long this goes on for; I never want it to stop. Eventually I'm begging him, pleading with him to put himself inside of me in a voice that I don't recognize as my own.

When he finally pulls on a condom and enters me, I lose all sensation other than the awareness of him filling me, touching me in places that feel as though they'd never been touched before.

We climax together and he falls onto me, sweaty and panting. With my hands and feet still tied, I slip into an exhausted sleep.

***

"Breakfast," he announces, waking me with a tray of fruit and a cream cheese and smoked salmon bagel. My hands and feet are free and I'm surprised to find that he's tied one of the ribbons around my hair.

"Wow," I groan. I don't normally eat breakfast but I've never felt as hungry as I do at this moment.

He picks up a pear and bites into it, lying at the foot of the bed, propped up with one elbow. I notice for the first time that he's wearing a suit.

"Listen. I've got to make tracks soon, important meeting, but I had fun last night, I want to do it again." On a Sunday? Fine by me, I think, but I'm actually supposed to have planted six hidden camera in your house by now. The thought puts me off my food.

"I'll just have a shower quickly."

"Of course."

I stare at myself in the huge mirror of his en-suite. My hair is a post coital mess and I've still got the cameras in the lining of my clutch. What were you thinking? I ask myself. I expected a bit of fooling around, a pool party, then Tina and I would make our excuses and make a hasty exit, not this.

So why don't I regret it?

"Can I give you a lift anywhere?" he asks, the second I'm back in the room.

"I'd prefer to walk," I reply, "I need the fresh air."

By the time I've got last night's dress and knife-like heels on, he's already ushering me out of the house with a brief kiss goodbye on the cheek.

Once his car is out of sight, I go back to the house across the street where our team is monitoring his every move. They stare questioningly but I get the first word in, "Someone had better follow him, he's in quite a hurry."

"You've been in there all night? Why didn't you set the cameras up?" asks Dave, incredulous.

Sorry Dave, I was busy having the most mind blowing sex of my life, I think.

"I didn't get the chance, he didn't leave me alone for a second."

Tina sniggers and I glare at her.

"Doesn't he sleep?" asks Dave.

"Not a wink, he must have taken something," I lie.

"Well, do you think you'll get in there again?"

"I'm sure of it," I reply, with complete sincerity.

"I want to know everything," hisses Tina, but I ignore her.

***

I'm back in Marc's house, sat on his marble kitchen counter with him still inside me, having reached a shuddering climax. He's pushed my knickers aside and his trousers are down below his muscular arse. He'd barely offered me a drink before he lifted me onto the counter.

I've been posing as a personal trainer in a nearby park for nine weeks, so when he recognized me on his morning run he realised why my face was so familiar in the club on Saturday, he's seen me commanding a group of three to do squats and press-ups for months. He stopped me in the middle of the session and asked me to come round tonight and I promised myself that I'd keep my wits about me this time. When I disappear from his life forever, he won't be able to find my clients to question them, they're all undercover like me.

"I'll tell you my fantasy," I whisper, nibbling on his ear, "I want to do it on camera."

"Get ready then," he demands, lifting me down to the floor in his strong brown arms.

I'm kneeling in the center of his bed in carefully chosen Agent Provocateur lingerie when he comes into the room with a video camera and a tripod. Someone's done this before, I think.

"It's your turn," I say, pulling his T-shirt off him and tying his wrists to the bed. I take his trousers and boxers off and feel a shiver of excitement at the sight of him, hard and pulsing again.

I take him in my mouth and run my hand up his smooth, sculpted chest as I suck and lick, feeling myself get more aroused with each of his groans.

When he's on the brink, I climb on top of him and order him to wait, rocking back and forth as he fills me, reaching every hidden spot.

He breaks his hands free of the ribbon with a tear, cupping my breasts and groaning, his urgency making me feel even more turned on. He runs his hands down onto my waist and moves me up and down to his own perfect rhythm. As soon as I begin to climax, he gasps with relief and finishes with me, eyes clenched.

Before long he's fallen into a sex-worn sleep with his heavy arm lying across my back. Once I hear his breath reach a slow, steady rhythm, I slide out from underneath him and slip my clothes back on, my body still tingling with passion.

I make my way quietly upstairs and finish my assignment, placing cameras in a bookcase in his study, in his black and chrome kitchen and the fireplace of his living room. I bug the phone and find the painting that hides his safe, making a mental note of the type of lock so that I can report back to Dave.

After creeping back down into the bedroom, I look over at his sleeping body, the sheets tangled around his waist, exposing his beautiful frame. I take the memory card out of the video camera.

I might never be able to have sex with Marc Burgess again but at least I'll be able to relive it now.