Just a quick note for this chapter – I don't know very much about the health service or mental health services so I apologise if I've got it wrong, I don't mean to cause any offence! Thanks so much to you all for your support so far with this fic, you've really helped spur me on – hopefully it won't be too long before it's finished now! x

Friday, 9pm

"Boss?" Spence's dark head appeared around the door frame of Boyd's office, rousing the older man from his thoughts. "We've got it – Barry Peterson was definitely working on the house where Mary Hammersmith was found."

Boyd stood up, removing his reading glasses as he did so. "There's a big surprise, Spence."

"You'd be a millionaire now, if you'd put a bet on it. I think we all would be."

Boyd began walking towards the main meeting room, following Spence to where Frankie had joined Mel and Grace.

"We need to bring Peterson in." Boyd said evenly, addressing the group. "I think we have enough to charge him."

Mel sighed. "It's all circumstantial, though, isn't it? I mean, just because he was working at the house doesn't necessarily mean..."

Boyd's thin veneer of calm was suddenly shattered. "Oh, come on, Mel! He's working at the house where one twin was murdered and the other twin then just happens to turn up as his wife?! Give me strength!"

"I'm just thinking of evidence, Boyd, solid evidence! We've got to make this stand up in court otherwise what's the point?"

"The point is, Mel, that once we have him in custody, we can worry about it then!"

Mel shook her blond head vehemently. "That's totally backwards and you know it, Boyd. We won't be able to make the charge stick."

"She's right." Spence added. "He'll walk as soon as he gets his Brief in here."

Grace nodded. "I agree..."

Boyd raised an eyebrow at her. "Is this a mutiny, then, or what?"

She tried not to smile as she looked at him. "I think we at least have enough to bring him in for another interview. See how he reacts when we put some questions to him."

"This isn't a democracy, you know, Grace, I'm the one who makes the decisions in this room..." His expression was stern but his dark eyes were shining.

She rolled her eyes. "Hmm, I know you'd like us all to think you're a bloody tyrant..."

"...but, as it happens, I agree." He turned to the other man. "See to it, Spence. I want him in here by the morning."

Spence picked up his phone and began to dial. Boyd's attention shifted to Frankie. "Is there anything you can give us forensically that can tie Peterson to the murder, Frankie? Anything at all?"

Frankie shrugged, tucking a stray strand of dark hair behind one ear. "I lifted several alien DNA samples on my second pass through the items found with the remains. If I could match Peterson's DNA to one of those profiles, I'd say you'd have a pretty good case."

"Great. I'll get a sample from him when he comes in."

Grace took a breath to speak. "If he is guilty, Boyd...there's some pretty complex psychology going on. I mean...has he kept Susan a prisoner all these years?"

"What, and just faked the memory loss thing? Wouldn't she have to be in on that?"

"No, not faked it. Took advantage of it. Susan was probably so traumatised by what happened to her sister..."

"What he did to her sister, Grace..."

"...that she may well have buried it so far in her subconscious as for it to be unrecoverable. He may have taken advantage of that, invented the whole story about rescuing her from the streets."

"So, what does that mean, Grace? Has he been abusing her for forty years?"

She sighed. "It may have started out that way but...I don't know, I think he genuinely cares for her."

Boyd snorted contemptuously but Grace continued. "And, what's more, I think he genuinely cared for Mary too."

"For God's sake..."

"You remember the way her remains were left? Carefully buried with her possessions? That's not the work of someone who was cold to their victim..."

"He smashed her skull in, Grace! Or have you conveniently forgotten that fact?!"

Grace threw up her hands. "I'm just saying it's a discrepancy. The killing was angry, full of rage but...the burial...it was something else, Boyd. It was gentle."

"Oh, yeah, he's Father bloody Christmas, isn't he."

"It's just something to consider. Before you go in all guns blazing."

Boyd sighed loudly and held her gaze for a long moment. "Fine..."

"I think we should continue to make checks on him as well, see if we can work out what makes him tick."

"What did you have in mind, Grace?" Mel asked, picking up a pen in her slender fingers.

"His family, anybody connected to him back in 1964."

"It's a waste of time." Boyd called over his shoulder as he strode back towards his office. " I'm telling you, it's an absolute bloody waste of time."

Grace rolled her eyes. "It's worth a shot. I still say there'll be more to this when we scratch the surface."

Mel gave her a small smile. "I agree. I'll dig a bit deeper, see what I can find."

"Thanks, Mel." The profiler yawned, standing up from her chair. "In the meantime, I'm going to head off. I'll see you all in the morning."

"Bright and early." Mel chirped.

"Well, early, at least." Spence added. "I'm not so sure about the 'bright' bit."

Grace smiled. "Don't stay too late, eh?"

Mel shrugged, gesturing with her head towards Boyd's office. "You know what he's like. We'll be lucky if we're out of here before midnight."

Spence yawned loudly. "Yep, then we can hit the all-night clubs and be back in here by dawn."

Grace patted him on the shoulder. "I think you're passed all that, Spence, by the look of you."

"Nah, I'm raring to go, me."

She laughed, beginning to head towards her office to collect her bag, stopping as Boyd called her name, his voice carrying into the main meeting room. She peered around his door, eyebrows raised in question.

"You going home?" He asked.

"Well, I can't achieve anything here until tomorrow and besides, I..."

"What? Some sort of hot date lined up?" He lowered his eyes, unable to meet her gaze as he voiced his internal fears.

Grace looked at him, surprised at his question, her heart thudding inexplicably harder in her chest. "No. I was going to say I'm knackered and I'm going straight to bed. That all right?"

Oh, God, you in bed...what are you trying to do to me, Grace?...He gave her a slow smile. "Perfectly all right."

A frown flickered across her features as she tried to read the meaning behind his words. "Good. I'll see you in the morning."

"Sleep well."

The creases on Grace's forehead deepened, confusion pervading her mind as she walked from the building. Now, what the hell was that all about? She sighed, shaking her head. I don't know why I'm surprised, she mused, it's not like Boyd's ever made much sense... The thought made her smile ironically as she made her way home.

Saturday, 10am

Boyd stood staring into the interview room through the observation glass, his arms folded across his broad chest, a brooding frown creasing his forehead. From his seated position inside the interview room, Peterson was calmly drinking from a cup of water, pointedly glancing at his wrist watch every few minutes. Boyd took a deep breath to collect his thoughts before addressing the petite woman at his side.

"What do you think, Grace?"

Grace gave a small shrug. "Well...he looks relaxed...I mean, he's pissed off that you're keeping him waiting but...he doesn't look particularly nervous, Boyd."

"You mean he doesn't look guilty?"

"I didn't say that. But he does look in control."

"Is he going to try and manipulate this interview?"

"He's intelligent enough, certainly."

"Yeah, well, we'll see about that."

Boyd moved to walk towards the entrance to the interview room but Grace caught his arm. "Don't bully him, Boyd..."

He closed his eyes briefly. "Oh, Grace, not now..."

"You won't achieve anything. If he is guilty, there's a deeply complex psychosis at work here."

"I've got to get him to talk. Even if he's not guilty, he knows something, Grace."

"I agree. But shouting him down isn't the answer and as for hitting him..."

Boyd turned towards her. "I've got no intention of hitting him." He said evenly.

Grace sighed. "You never have the intention, Boyd, I'm sure of that...but sometimes you..."

"Sometimes it just happens. And sometimes it works."

"Boyd..."

He pulled away from her, tearing his gaze from hers but she managed to grasp his hand as he moved past.

"Boyd." She whispered again, her deep blue eyes imploring him. "Please. Don't do anything you'll regret."

He gave a hollow laugh, shaking his head. "I never do anything I regret, Grace. You should know that by now."

He strode away from her forcefully then, trying desperately to banish the feel of her soft skin against his as he stepped into the interview room. Peterson glanced up at once.

"Well, it's about bloody time, Superintendent." He said irritably. "You've got no right to keep me waiting like this, I'm here voluntarily..."

Boyd began pacing in front of his suspect. "You're here, Mr Peterson, because you've turned out to be of major interest to my murder enquiry."

Peterson gave a contemptuous snort. "If that were true, you would have arrested me, surely."

"I just want to talk to you, Mr Peterson..."

"You mean you haven't got enough evidence against me, isn't that right?"

Boyd let the man's question go unanswered as he took a seat opposite him. "You were working on a house in Kensington in 1964."

Peterson laughed. "I worked on a lot of houses in 1964, Superintendent. What's your point?"

Boyd took a breath, attempting to calm his annoyance. "My point is, Mr Peterson...the house you worked on just happens to be the one where the remains of Susan's twin sister were found. And since I don't believe in coincidences, I'd say that makes you inextricably involved with her murder."

"Oh, that's outrageous..."

"Well, can you explain this apparent coincidence, then?"

Peterson fixed him with a cold stare. "It's exactly that, Superintendent. A coincidence, nothing more."

"And is it also a coincidence that you ended up married to this murdered child's twin?" Boyd laughed mirthlessly, dangerously. "What do you take me for, Mr Peterson?"

"I'm telling you the truth, Superintendent. If you don't believe me, that's your problem, not mine."

"Wrong, Mr Peterson. You couldn't be more wrong about that."

Peterson sighed loudly. "What more can I tell you?"

"You can start by telling me exactly what you were doing in that house in 1964."

"You're going to have to be a bit more specific, Superintendent."

Boyd removed his glasses from his pocket and consulted his notes. "Twelve Primrose Avenue, Kensington. Don't tell me you don't remember, Mr Peterson, because I won't believe you."

Peterson held up his hands. "I'd need to have a look at my records. That's the truth, Superintendent."

"Oh, come on! You know damn well which house I'm talking about, Mr Peterson, because you killed Mary Hammersmith and buried her in the back garden there!"

"Boyd, for God's sake, what the hell are you doing?!" Grace's voice reverberated loudly via his earpiece but he ignored her protests studiously.

The older man in front of Boyd bristled visibly, colour bleaching his pale cheeks. "You can't just go accusing me like that, where's your fucking evidence?!"

"Until you can give me the specifics of what your work on that house entailed, I'm going to carry on accusing you, evidence or not!"

"That's completely ridiculous! I want to phone my solicitor!"

"You're not under arrest, Mr Peterson..."

"Then stop accusing me, Mr Boyd. Or else arrest me and let me get my solicitor."

A voice sounded in Boyd's ear then, Spence's deep baritone, and he turned towards the observation window. "Boss. I need a word."

Boyd rose silently from his chair, ignoring Peterson's notes of protest as he stepped from the interview room, the door slamming loudly behind him.

"Yes, Spence, what is it?" He asked, rubbing a frustrated hand across his face and trying to block Grace's dark expression from his view.

"I've got some news on Peterson's background." The junior officer said.

"Well, come on, man, don't draw this out any further! Give me something I can charge that bastard with!"

Spence shook his head. "I'm not sure I can do that, sir."

"What?! What do you mean?!"

"Barry Peterson has a son, Matthew Edwards, born 1954, who was living with him in Barnet in 1964..."

"Is this going somewhere, Spence? Because I've got a suspect in there who we're in serious danger of losing..."

Spence blew out an angry breath. "Matthew Edwards was sectioned under the mental health act when he was seventeen. From what we've been able to uncover, he claims his father abused him..."

Grace squeezed her eyes closed, a pained expression marring her features. "Oh, my God..."

"What, so he practised on his own son first before turning his attention to the Hammersmith girls?! This bloke just gets holier and holier, doesn't he." Boyd said, his flat voice barely containing his fury.

"What was he sectioned for, Spence?" Grace asked quietly.

Spence shook his head. "I dunno. It's red tape central with the health service, Grace, especially where mental health is concerned."

She nodded. "I'll see if I can have more luck..."

Boyd looked thoughtful. "His son was ten years old at the time Mary Hammersmith was killed...Jesus, is it possible he witnessed her murder? Witnessed his father cave in her skull?"

Grace shrugged, her expression grave. "That certainly might account for his mental health problems." She stepped towards him, resisting a sudden urge to touch him; his arm, his hand, his chest. "Let me see what I can find out before we jump to any rash conclusions, though, all right?"

"Fine." He said, darkly. "In the meantime, I'm going back in there."

He stalked back into the interview room, his body beginning to tremble with barely concealed rage. Grace turned to Spence, discomfort seeping into her bloodstream at Boyd's aggressive demeanour. "Get in there, Spence, I don't trust him alone with that man."

Spence nodded sharply before following in his boss' wake. Grace made her way swiftly back to the main meeting room, her heart rate quickening with each step.