Prologue:

The Locket

Tessa glanced at herself in the mirror as Sophie fussed about with her hair. Her hand was beginning to heal, though the tell-tale scars were painted across it. Still, she was glad when Sophie fitted kid gloves onto her, concealing it. She didn't want the marks of her anguish for the world to see, especially not Jem. Or Will.

'We're due for training today, Miss Tessa,' Sophie said cheerily, and Tessa could tell she was giddy to see Gideon.

'Cecily will be joining us for her first lesson today. I wonder how she will do,' Tessa said thoughtfully, thinking about Will's shocked expression two nights ago when Cecily strode in, disrupting their celebratory dinner. 'I imagine she will take to her studies quite fiercely.'

Cecily was a subject that seemed to be looming over everyone, especially Will. She had come in, demanding she be trained, and immediately Will had rushed her to sit down at the table in Jessamine's place to explain exactly what she was doing there and why now.

Will and Cecily then became involved in a lengthy discussion, which quickly escalated into a full-blown argument. After encountering the warlock Ragnor Fell, Cecily had been drawn to come to the Institute to see Will, and to receive an explanation about why he abandoned them, all those years ago.

At that moment, Tessa had been extremely anxious, looking at Will, thinking of the painful conversation they'd had when Will explained his curse. Then Will, amid a world of internal pain and suffering, eventually broke, and told everyone the truth. Why he had been so cold to them the past five years, everything.

Even so, Cecily decided to stay. She still insisted she wanted to be trained as a Shadowhunter, if not to get closer to Will. Tessa found this strange, and Cecily's real motives were still clouded.

Once she was changed, she headed down to breakfast. For some reason, nobody was there. Cyril came in, informing her Charlotte was ill due to her pregnancy, and a cold seemed to be running through the Institute, infecting everyone. Tessa could not hide the frustration in her steps as she swept into the drawing room, where a plate of sandwiches was lying on a silver platter. She sat herself down on one of the chairs.

'Tessa, my darling.'

It was Jem, admiration in his voice as he came to sit next to her. Tessa couldn't help smiling at him. His hair looked especially silver in the morning light, and his tenderness made her heart happy.

Yesterday, they had spent the day out in London, wanting to get away from the general mood of the Institute; even though wonderful things had been announced, they could sense the tension. It had been good for Tessa to do this; she could almost forget about Will if she got lost in Jem.

Cyril came into the room, and Tessa perked up, hoping he had come bearing news of either Cecily or Mortmain. Instead:

'Miss Gray, there is someone at the door who wishes to see you,' he informed them.

Tessa furrowed her eyebrows. 'Dear God. I hope one of my relatives hasn't come here wishing to be trained!' she exclaimed, but there was careful curiosity in her voice. 'May my fiancée come with me?' she asked, with a smile in Jem's direction.

Cyril shook his head politely. 'The person wishes for it to only be you, and to remain unnamed from the company of Shadowhunters here. My apologies, Master Jem.'

Tessa, with a puzzled glance at Jem, stood up and followed Cyril out of the room, towards the front door of the institute. To her surprise, standing there was Magnus, looking quite tired and frazzled. He seemed out of breath.

'Tessa. I have something for you. May I come in?' he panted, directing this towards Cyril, who nodded. He ran into the Institute, and beckoned for Tessa to follow him inside the first empty room he saw, which happened to be the strategy room, a large room with a few tables scattered around it, scrolls aligning the walls. Magnus slammed the door shut, and rushed to the table.

'I have been looking around for you, Tessa Gray, as your predicament interested me and I was drawn to know more. I'm immortal, and without Camille's restraints, I am free to prance around like a wild pony, absorbing as much information as possible. I talked to a few friends; Ragnor Fell, Malcom Fade, and Catarina Loss, and came across some interesting things. Though I haven't garnered any possible information yet, I have something to give to you,' Magnus told Tessa.

Tessa's chest tightened at the thought of knowing more about her origins. She yearned to reach out into Magnus's pocket, and to take the object for herself. But she knew, of course, this was not proper, so she instead spoke very politely.

'Well, Master Bane, I cannot thank you enough. You needn't have gone to all the trouble just for me. I can pay you, if you like,' Tessa said compassionately, though Magnus shook his head slowly as he fumbled in his pocket for something. When he finally found it, his cat eyes fell back into their usual, amused expression.

'No, no, I am quite grateful for this little affair. I have found out a few valuable pieces of information about myself too,' he said, with a dark satisfaction behind his eyes. Tessa looked at him incredulously, and then turned to the object he'd drawn from his pocket.

'It was found in Mortmain's family manor by someone who was part of the raid, I won't say who, and had earnt this as one of the spoils. Apparently, it hadn't been properly examined by the Clave, because it has demonic properties. It had the name Elizabeth Gray on it,' Magnus explained, both looking at it. It was a simple locket, with a rune engraved on the front she did not recognise, mixed in with a beautiful twisting pattern, as most Shadowhunter designs did.

'It's a dark object. The rune on the front is a demonic rune. I thought you would want it, knowing it was something of your mother's.'

Tessa stared up at him, anxious. 'But...what does it do? Who found it?'

Magnus sighed, still looking at it. It was hard to tear your eyes away, Tessa admitted. A dark power seemed to emit from it. 'As I said, I won't say who found it, but what all does it matter? They have kept it all these years, not knowing what it was, until I eventually saw the name, emblazoned in their spoils cabinets. It enhances your warlock abilities; I find myself quite jealous giving it to you, but I'm afraid it's yours. When wearing this, you will not fall out of your Change unless you will yourself to, if indeed it does work.'

Tessa took it, and fastened it around her neck. She now had three necklaces weighing her down: Jem's jade pendant, the clockwork angel, and this dark object. She immediately felt a dark power surge through her. She gasped, taken aback by the feeling. 'I-I feel different,' she said.

'Try and Change,' Magnus said.

Tessa didn't want to Change. The dress she was wearing right now would no doubt fall unflatteringly on anyone else, and Tessa didn't want to be humiliated this early in the morning in front of Magnus Bane. But she did it. For some reason, the first face she saw when she closed her eyes was Jessamine, eyes huge and scared in the Silent Brother's chamber. She reached out for her, but found she grasped her almost instantly, and she was thrown into the darkness that ensued when she was Changing. But this was only for a few moments, before the Change washed over, quickly and painlessly. She opened her eyes, and looked down at Jessamine's small body. She gaped at Magnus. 'It…it worked!'

She Changed back into herself, finding this was just as easy as going into it. The Change had felt different this time. Before, it was like she was holding onto something, grasping on to an edge that she could slip off. But now, it felt like she was sitting on the ledge comfortably, and to get back she just had to dangle her feet off and jump down.

Magnus was staring at her in amazement, before his face lit up with confusion. She suddenly felt a scratching at her chest, and she looked down. She saw, to her amazement, the clockwork angel at her chest fluttering up and down, trying to flit up from the locket hanging just below it. She opened her mouth, gasping.

'What's happening?' she asked frantically, as she clasped her hands over the device, to try and stop its urgent wings, persistently trying to get away from the locket, looming below it, a dark weight on her chest. She breathed heavily.

'Take it off,' Magnus said, his yellow eyes gleaming, and Tessa obliged gladly. When she lifted the locket from her shoulders, she felt as if a strong hold was being released from her, and she took a hand up to massage her chest, where it had been before. She had to admit she had been taken over by a dark satisfaction when it had adorned her, and felt a bit deprived without it on.

'That object, it has strong demonic power. Strange…because, if your necklace is repulsed away by it, then it must be manifested with some sort of angelic power,' Magnus said with his eyebrows furrowed, staring at Tessa's clockwork angel.

Tessa suddenly realized the clockwork angel she had always owned was a mystery she hadn't given much thought of yet. It had whirred to life more than once to save her life in times of dire need, when the threat of the automatons was fatal. It seemed like a guardian to her, always there. Magnus narrowed his eyes.

'I…please, take back the locket. I can't have it, if it means the clockwork angel will always be disturbed. Please, use it to find out more about my mother. I will consider the history of the clockwork angel with Henry, but these dark objects…I cannot associate myself with such things.'

Magnus looked at her, sighed, and then took back the locket. '

'But it worked, Tessa,' Magnus said with a dark glint in his eyes, and Tessa nodded, not sure what he was trying to say. 'You know what this means, right?'

Tessa shrugged her shoulders, a suspicion creeping up her spine. If it only worked for warlocks…

'Tessa, your father is a demon.'