A/N: I don't know how fast I'll be updating this given I have other projects that are a higher priority, but I'll try and aim for at least one chapter a week.


The trek back from Irkngthand was long and arduous, and for the last third of it, Brynjolf and Karliah had to load Rath onto a horse they'd stolen from outside an inn. Whatever Mercer put on his blades it did not heal easily, and she spent the first few days back in Riften huddled under the blankets on her bunk in the Cistern, alternately shivering and sweating with fever. Redguards were hardy but there were limits, and clearly Mercer had taken her heritage into account. Her arm and back itched under the bandages, and her misery was only lessened when her fever dreams saw fit to give her what reality had not; Mercer's corpse at her feet.

Eventually, her fever broke, and when she awoke again she was hungry for the first time in days. She wrapped herself in blanket and padded over to the fire to help herself to some stew.

Now her mind was clearer, Rath noticed how quiet the Cistern was, and she didn't think it was because people were mindful of her need to rest. Everyone kept their voices lowered and was wearing a slightly disbelieving look. Sometimes they stopped and stared at the guild vault, its doors gaping open still, their ruin displayed with an odd sort of defiant pride. There were no more secrets here.

The place felt empty. Rath had never known Mercer not to be there. Day or night, he'd either be scowling over the ledger – faking it, she knew now – or talking quietly to the others or even catching a couple of hours sleep in one of the bunks. His was a presence that had filled Cistern like the night fills the sky and his absence was glaring.

She kept expecting him to be there every time she glanced over, but it was Brynjolf who now sharpened the quills and kept the numbers.

She lay on her bunk holding up her battered journal, the candle on the bedside table casting a flickering light over the untidy scrawl of her own writing. She braced the book on a raised knee and scribbled over a couple of lines:

Retrieve the Skeleton Key.

Escape from Irkngthand.

Almost everything else on the page had already been crossed out firmly with ink or charcoal. Only one line remained untouched, right in the middle of the page.

Slay Mercer Frey.

She couldn't cross it out until she knew for sure, and she'd never know. Rath bared her teeth and then tossed the journal down on the rumpled furs and blankets. She was sick of lying around, sick of sleeping, and most importantly she was sick of seeing Mercer's face every time she closed her eyes, his expression murderous but otherwise unreadable. She pulled on some clothes and, still barefoot, padded over to Brynjolf.

"Feeling better, Lass?'

She swung her arm, and twisted slightly, feeling the healing wounds pull at her, but it was a clean, pleasant pain as opposed to the puffy, stabbing heat of the last few days. "I'll live," she said.

"There's no rush if you need more rest."

"The last thing I want is more rest. I need to do something. Anything. How's the guild?"

"No worse than it was before, really. We just all now know there's no gold in the vault for an emergency. Don't fret, Lass. We've been getting by, getting better even; we'll pull through."

Rath sighed and they both stared at the empty vault for a few moments.

"Have you given the Key a try yet?" Brynjolf asked.

"Good idea."

She fetched the Key from her pile of belongings and Byrnjolf and Cynric followed her into the training room. Niruin was already in there, practising his archery like he did every day, but he put his bow away and joined them at the practice locks when he saw what was going on.

Click ker-thunk.

"Well, that was an easy one," Cynric said.

Rath merely nodded and moved to the next one. As more and more locks fell open other thieves began to join them, and soon the training room was full, and each click ker-thunk was greeted by appreciative murmurs.

It was as if the tumblers just fell into place, like the Key had an attraction to the metal that Rath, for all her years of picking locks, couldn't explain. Eventually, she ran out of locks.

Then people spread out and started finding more; chests they'd lost the keys to, practice locks nearly rusted shut and forgotten, and even a lock Rune had once hacked out of a door with an axe when he couldn't get it open any other way. The Skeleton Key opened them all.

Vex folded her arms and leaned against the wall, "Well, it's no surprise that he was tempted by the vault. I just wonder what else he used the Key to steal over the years without telling us."

"I think it's a shame you're supposed to just put it back," Cynric ventured. "Seems like a waste to me."

Silence fell as everyone looked at Karliah, who'd been sitting quietly off to one side, watching without comment.

"What do you expect me to say?" she asked. "Whatever you do, there is always a price."

"What are you going to do, Lass?"

Rath turned the Key over in her hands.

"I'm going to see what else the Key can open, maybe take something nice." She shrugged, "And then I'll give it back. The guild doesn't need it to prosper."

It was an answer that seemed to satisfy everyone, including Karliah, and with the show over the thieves dispersed.

Rath stitched up her Nightingale armour and started packing supplies. She threw her journal in on top while Brynjolf watched her.

"Where exactly are you going?" he asked.

"I don't know exactly," she said. "Not far. I'm fine. Thank you for your concern."

He accepted her dismissal with a shrug and strolled off towards the Flagon. Rath left via the graveyard entrance.

Hours later, Rath slumped against the cold rocky wall of the tomb and with gritted teeth fought back tears of frustration.

"How?" she muttered. "Just fucking how?"

Behind her were the ruined traps and gutted remains of draugr that had been guarding Forelhost. In front of her was a puzzle door. It was just like the many others she had unlocked with claws, and much like the one she had seen Mercer open unaided.

She had the claw, but had no interest in using it.

The Key simply didn't work. It couldn't work in any way she could see. There were three holes. One key. Even using the Key in one and trying to pick the others didn't work, and Mercer clearly hadn't done anything as complicated as that.

She thought back to their time in Snow Veil Sanctum. She'd been full of adrenaline, and determined to track down whoever was attacking the guild. She'd been full of admiration also, for her guildmaster. Part of her later rage was fuelled by how easily she'd been swept along by his patter.

He'd said the doors had a weakness, but later she'd just assumed he'd used the Skeleton Key. But the Key didn't work. She gazed up at the door and ruffled her hair irritably. He'd made it look effortless, like all it took was a flick of the wrist.

And she'd believed it! Stupid!

"Focus, Rath. Think logically." She had to calm down if she was going to work things out. She'd never actually tried to pick one of these locks before. Conventional wisdom was that they couldn't be picked, and usually she found a claw to open them anyway. She opened her pack, took our her journal and a stick of charcoal, and turned to a new page.

Her stomach was rumbling and her torch was burning low when she gave up. Her fingers were black with charcoal, her eyes were blurry, and she'd covered three pages in an attempt to map the lock's inner workings by feel alone. She'd broken seven picks in the door, and she still had no idea how it worked. The three parts of the lock were connected, shifting part of one changed the others, and attempting to track this movement was driving her mad.

She gave up for now, dusting off her hands and taking some strips of dried venison from her pack and chewing on them stoically. She'd tried the holes for the claw. She'd tried the puzzle mechanism around the lock. She couldn't think of what she'd overlooked.

She followed the venison with an apple and some water, and closed her eyes, letting them rest for a while. Her thoughts were not so easy to still; round and round they went.

It had to be the Key. There wasn't anything else. Had to be.

Once she'd rested for a while, she stood up, took a deep breath, and tried again with the Key, calmly, methodically, and rationally. At least at first.

"You useless piece of junk!" she snarled, hurling the Key across the room. It bounced off the wall and clattered to the stone floor.

"Heh."

Burning frustration instantly evaporated into icy calm, and she drew her blades in one fluid movement, her breath stilled in her lungs, her feet braced. She wasn't even sure that she'd heard anything. She'd been working for hours and she had no idea what time it was. It was possible her mind was playing tricks.

But it had sounded like a cough of contemptuous amusement, one she'd heard before, and one she'd recognise anywhere.

Mercer.

She drifted forward, silent as a cloud shadow, sharp as spite, her eyes narrowed against the dim light as she focused on the darkness. Not so much as a creak of leather gave her away as she stepped forward. Exhale. Step forward. Inhale.

For the first time since she'd arrived in Skyrim, she realised just how far away she was, not just from Hammerfell, but from anywhere. No one knew where she was. No one would ever know if she died here.

Step forward.

Nothing had been disturbed. Even the dust and spider webs were still. She picked her way around the fallen draugr.

Still nothing. Utter silence shrouded the tomb. Methodically Rath prowled Forelhost's forgotten halls, leaving no alcove overlooked and no passageway disregarded at her back.

When she found herself back at the front door, she cautiously allowed herself to relax. Maybe she had just imagined it. She couldn't blame herself too much; she'd had Mercer on the brain lately.

Still quiet, but more swiftly now, she hurried back to where she'd left her things. She'd leave the door for another day; she clearly wasn't making progress, and she didn't care too much what was on the other side of it.

Maybe Karliah would have some explanation-

A cool breeze, redolent with the unmistakable old meat scent of Nordic dead, washed over Rath's face. She shivered and stared dumbly for a few moments at the puzzle door, now gaping open, and the dim light filtering in from the passageway beyond.

"Shit!"

She dashed forward, leaping over a pressure plate just in case it had been reset, skidding to a halt just in front of the door and casting about frantically for the Key.

The Skeleton Key was lying where it had fallen. She regarded it carefully before touching it, but something told her it hadn't been moved. She snatched it up and stared at the open door, every nerve ending straining to try and discern whether or not she was alone. For a moment nothing moved, and then the breeze from the doorway ruffled the pages of her journal still lying open on the floor. As she stooped to pick it up, the Razor in her right hand still drawn, she caught a glimpse of a phrase right in the middle of the page.

Slay Mercer Frey.