Mac glanced up at the sound of a throat clearing.

'Hey Mac. Have you seen Stella?' Adam asked.

He sat back, frowning. 'No but I assume she's working on the evidence.'

'I checked. Nobody's seen her for a while.'

'What about...' Mac started, feeling a sense of nervousness build within him.

'Lindsay checked the ladies'. There's no sign.' Adam spoke with a building panic in his voice.

At the obvious concern of his employee, Mac stood up and walked with him. 'Ok I'll look too. I'm sure she'll be around.'

At that moment Mac was unsure if he was persuading Adam or himself of that fact.

As he walked down the corridor he was stopped by Jo who noticed the visible concern on her partner's face. 'Hey Mac. What's wrong?'

'Have you seen Stella?' Mac asked, desperately attempting to hide the deep-rooted worry he was experiencing.

'Not in three hours. She was heading out to interview Maggie Thomlinson.' At Mac's blank look, Jo elaborated. 'She's the wife of Anthony Thomlinson who was interviewed at the time of the initial killings and who admitted to having an affair with the fifth victim Kate Cohen. Turns out he has quite a record of violence and suggested psychopathic tendencies. Stella said she'd head over there.'

'Mac what's wrong?' Jo could see Mac's increasing agitation.

'Nobody's seen her in three hours. I last saw her in the lab after she'd returned from that interview. I have a feeling something's happened.' Mac admitted and Jo quickly got to her feet.

'Get Adam to track her cell. You and I can go and find what Stella was last working on.'

Mac mutely nodded; a sense of panic and fear rising within him that he had not felt since 9/11.

Within ten minutes Stella's last minutes in the lab had been ascertained. Mac and Jo had discovered that Stella had found that the bladed tip belonged to a javelin and judging by her last search she had headed to the address of Anthony Thomlinson's brother, Damian. Like Stella had done so, Mac and Jo had noted the worn out and almost derelict appearance of the house. As they neared the front door they noticed that it was in fact pushed open and both raised their guns in anticipation for any possible assault.

'NYPD.' Jo shouted but received no response.

'Stella?' Mac called but again only silence greeted him. They walked further into the corridor before Jo stopped suddenly pointing at something on the ground. 'Mac, look.'

Mac's panicked heart thudded faster as he saw what she had found. 'That's Stella's phone. She was here.'

They turned as Angell entered. 'I've checked the house, there's nobody here. I think we can assume Stella's been taken.'

And with those words, Mac knew that his worst fears had been realised.

'Sir.' One of the techs called to Mac.

'What is it?'

'This came for you.' He handed him a box and left.

Mac frowned as he eyed the box. He was unaware of any expected delivery for the lab, and he certainly was not expecting a personal package. He ripped off the brown parcel paper and opened the box. It was then that the world seemed to freeze as Mac stared in acute horror at its contents. It was an NYPD badge covered in blood. Mac knew from his brief glance of the numbers who it belonged to and he felt a wave of revulsion pass through him.

On seeing his obvious distress, Jo also frowned. 'Mac what is it?'

'It's...' He strengthened his voice. 'It's Stella's badge.' And the others gasped in horror as they also saw the blood which coated the badge.

'We have to find Stella.' Was all Mac said and he turned, prepared to flee to the privacy of the men's room. However Stella's cell burst into life then and the CSIs turned transfixed at the device. Mac leant over and put it on speaker. He cleared his throat. 'Stella?'

'Afraid not, Detective Taylor.' The voice which greeted him was like knives scraping on metal. It almost sounded synthetic, although a machine was speaking and not a human. However Mac knew all too well that it was a human's voice. The voice belonged to a man who had been so badly burned in a car accident that he had suffered permanent damage to his vocal chords.

'Who am I speaking to?' He pretended to be naive.

'I think you know fine who this is Detective.' By this point Adam had begun his triangulation of the cell's signal, trying to find a location.

'I do but I would like to know how to address you.' Mac stated calmly, using all his willpower not to lose it and demand answers for Stella.

'You may address me as the Taunter.' At this confirmation, the others stiffened and a deathly silence had befallen the lab as everybody listened in fascinated horror. 'I can see you are all familiar with my work.' A cold, maniacal laugh followed. 'I take it you have received my little gift?'

Mac glanced down to the badge in his hand and felt fury course through his veins.

'Where's Detective Bonasera?' Mac asked coldly.

'Now that's interesting.' The Taunter wheezed.

'What is?' Mac snapped.

'Your concern for her. It seems strange considering you're no longer partners. But I'm touched that you reunited to chase me.'

'Where's Stella?' Mac's voice was ice.

'I'm afraid you'll not be seeing her again...well at least not alive.' Another bout of choked laughter followed. 'But don't worry, I'll be sure to tell her you said hello.'

It was then that Mac lost his temper. 'I promise I'm going to find you and if you've hurt Detective Bonasera in anyway...'

The call disconnected.

Everybody glanced to Adam who shook his head. 'I'm sorry Mac. The signal kept bouncing, I couldn't get an exact location- all I got was she's in Lower Manhattan. I'm gonna keep looking in the local area and see if I can narrow the signals of calls in that vicinity for the time.'

All Mac could do was mutely nod.

Once all available police personnel had been mobilised in the search for Stella, Mac turned and disappeared from the lab, heading to the rooftop for some air and time alone to think about the next steps in the search for Stella. Not since the tragedy of 9/11 had he felt so helpless. He had promised himself then, as he combed his way through the dust and debris, looking for any sign of Claire, that he would never again be so vulnerable and helpless. But now he was utterly helpless. Even despite the fact he was chief CSI and a good detective it just wasn't enough.

Stella had vanished; taken under his very nose. He had failed her; he should have ignored her protestations and assigned her protection anyway. But a little voice inside his head told him that that action would have been fruitless. It was obvious the Taunter had been shadowing Stella for some time to know about the conflict in their relationship and therefore it was only reasonable to conclude that the serial killer would have done anything in his power to get Stella for his twisted aims.

All thoughts about what the psychopath would do to Stella sickened him. He couldn't bear the thought of her being hurt in any shape of form. Her kidnap was his fault; if only he'd fought harder to keep her safe, if only he'd made sure she'd never left the lab in the first place. Mac felt tears burn his eyes.

They had to save Stella.

His breath came in short bursts as his pulse raced as images of all the Taunter's victims flashed before his eyes. Each and every one of them had endured excruciating agony before their deaths and the thought that Stella was in store for that was sickening. Mac couldn't get the picture of her lifeless corpse out of his head and he vowed for that never to happen. He would die before he allowed Stella to be killed. He had to find her! He had to! And yet he had not a clue where to start looking.

Mac tried to slow his breathing; tried to calm down. He knew from experience that panicking would only worsen the situation. He had to focus on finding Stella. But as he thought of her, the sickening panic returned and again he concentrated on his breathing. He clenched his fists tightly, another mechanism he used for coping with stress.

Approaching footsteps alerted him to the fact that he was no longer alone on the rooftop and he turned to be greeted by Flack.

'Detective Flack what...'

'Mac we need to talk.' Flack interrupted and Mac immediately fell silent on noticing the conflicted look in his friend's eyes. 'It's about Stella. You need to know the truth.'

'What are you talking about Don?'

'I'm talking about the real reason Stella resigned.'

In the following minutes Mac experienced a wave of emotions unlike any he had felt before. What Flack spoke of had turned his world completely on its head and he was reeling from the implications of it. All this time; for so many years he had been a coward. He had bottled up his emotions so much so that he had been terrified to admit the truth to his partner- that he loved her. And all this time, Stella had loved him and she had been alone, thinking that he had did not care. And to think that in one moment of utter madness he had lost the chance to rectify his mistakes and persuade Stella to stay. Until his dying day he would regret striking her. It was a horrifying act and one he could never forgive himself for. Once Flack fell silent, Mac just stood in shock for a long minute before eventually he managed to speak, his voice hoarse with raw emotion.

'Stella...Stella left because she loved me?'

'Yes. She's hurting Mac- still is. She loves you and has done for a very long time. She just wants you to be happy. She's willing to give up her happiness for you.' Flack explained, commiserating slightly with Mac as he could see the utter devastation this revelation had caused.

'God I'm such a fool.'

Flack nodded his agreement.

'I honestly thought Stella didn't love me. I honestly thought she just saw us as partners...I didn't realise she felt the same way.'

Flack looked utterly shocked at Mac's admittance. 'Are you saying that you love Stella?'

Finally Mac admitted the truth. 'Yes. I've loved Stella for so many years. I just...I was stupid...I thought she'd never feel the same way I mean look at her in comparison to me. She's too good for me.'

'You know Stella said the exact same thing about you.' Flack admitted. 'I'm the first to admit you've been a fool Mac, and I still can't forgive you for striking Stell. But what I will say is this- if you truly love her then tell her that. She can't continue to live like this Mac. She deserves happiness- you both deserve happiness.' Mac absorbed every word of his friend's speech. 'Now we're gonna go and find Stella ok? And then you'll have the chance to tell her the truth.'

Mac nodded fiercely in response as Don's words had sparked in him a sense of determination. They would find Stella and then he would spend the rest of his life showing her how much he loved her.