Sophie was ten when she found a brass cryptex in her father's bedroom. Nikola had been gone for a few days on a mission, giving his daughter plenty of time to rummage through his room. She would have preferred to explore his lab, but he had locked the door and neither Helen nor Henry would have consented to let her into his inner sanctum. It was fine though. Her father's bedroom was by far less interesting than her mother's. There were no pictures whatsoever, of course no jewelry she could steal for herself, no strange trinkets to fidget with, but there were tons of journals to read, if you had the gift to understand Tesla's thought process.

Alice had helped her to open the drawer of his bedside table. That's where they had found that strange puzzle.

"What is it?" She asked as Sophie extricated it from between an ink pen and a corkscrew.

"I don't know. It looks like a Chinese puzzle."

They sat on Nikola's bed, and turned the object around, analyzing it.

"There are letters all around it, and they move." Alice said, rotating one of the brass lines of code. "You can write words with it!" She exclaimed, her brown eyes lighting up with excitement.

"It looks like a padlock, you know, the ones with the numbers?" Sophie said, observing the cylinder closer.

"Yeah it does, but it's not keeping anything locked up." The brunette answered, her eyes riveted to the mysterious object.

At that, Sophie stopped fidgeting. What if it did keep something locked up inside of it? After all, the artefact was big enough to hold something small, like a secret treasure map or a key. She gently pushed Alice's hands aside and shook the cryptex, only to hear a clear tingling of metal against metal. The two girls exchanged an excited smile.

"There's something inside!" Alice squealed, her piggy tails flying around in a crazy wave of black hair.

"It sounds like a key or something." Sophie assented.

She stopped jiggling the cryptex to focus again on the code.

"We have to find the password to open it. What could be the code in six letters?" She wondered, turning the rings randomly.

Alice counted on her fingers, frowning, and her face lit up.

"Sophie is a six letter word." She suggested, shrugging.

Her friend pursed her lips.

"That would not be a good one, would it?"

"Come on, let's try" the youngest insisted, taking the cylinder from Sophie's hands to start turning the rings.

Sophie let her friend have a go with their new toy. But knowing her father, there was no way his password would be so simple. She was both thrilled with their discovery and the challenge it provided and defeated, as she realized her father probably had set his password with random letters, making it nearly impossible to crack.

When "Sophie" was entered on the cylinder and nothing happened, Alice let out a sigh.

"That's not it." She declared.

"If you want to try simple passwords, try 'pigeon'. It does have six letters, and dad loves them."

Alice set to work again, only to be defeated by the cryptex a second time.

"Do you think it could explode after three tries?" She wondered, suddenly very motivated to stop touching the thing and let Sophie have a go at it.

The curly haired huffed.

"Don't be silly. These things only happen in spy movies." She lectured in a reassuring tone.

"Can't you work your magic to open it with your powers?" The brunette asked.

"They are not powers, they are abilities." Sophie reminded her before she realized her friend was mimicking her, mouthing her words.

Alice burst out laughing.

"I'm sorry, you always say that. But to me you're a superhero." She explained with a loving smile.

Sophie rolled her eyes.

"You spend too much time with your dad." She chided.

They fell silent. She had used her magnetism quite frequently to unlock doors to forbidden areas quite a lot in the past. And although it was a fun thing to do, the last time had brought her quite a lot of problems, ending with Ashley's death and her own brain loaded with memories of things she had never done and people she had never met. Her mother and Will had done their best to help her try and partition her brain to sort her memories, but it was still hard for her to figure everything out. The more the time passed, the more she was starting to feel confused in her feelings, and she felt exhausted and overwhelmed rather frequently. She had promised herself that she would never use her abilities again, as all her problems sprang from them, and as she had seen how it had turned out with Ashley, but now? She was rather tempted to use Alice's idea. After all, she was absolutely certain they would never find the password by themselves.

"Shall we try once again with a password? It would ruin the fun if I used magnetism right now." She suggested.

Alice had a side smile as she nodded.

"What about the doc's name?" She asked.

"Helen is only five letters." Sophie pointed out.

"Right but she must have a nickname. What does your dad call her? Honey? Sweetie? Doc…" she hesitated "dockey?"

Sophie raised an eyebrow.

"Helen. He calls her Helen. Because that's her name, duh."

Alice pouted.

"Your parents are not fun."

They were fun. But not very demonstrative. Once, Sophie had enquired as to why her parents did not call each other sweet names. Her father had told her that the prettiest and sweetest name was the one they had been carefully chosen by loving parents and given at birth. Calling each other by their name was, he thought, like paying a tribute to their long-dead parents.

"Plus," he had said, "who calls me Nikola except for your mother?"

"Nobody?" Sophie had answered, searching for that data in her mind.

"See? Only VIPs call us Nikola and Helen. These are very intimate nicknames."

"Let's open it." Sophie declared, focusing on the cryptex.

Alice fell silent, knowing her friend would have to spend all her energy and ability to focus on her task. She looked at the artefact as the first ring turned seemingly of its own will.

At first, Sophie wasn't able to make more than one ring of the cryptex move. But it didn't stop on any combination and she understood she had to move every brass ring at the same time. She sighed, cringing from frustration, and closed her eyes, focusing harder than she had ever had to.

"It's working," Alice whispered as she saw all the moving pieces of the tube trying to assemble the password.

"No it's not." Sophie answered, opening her eyes and throwing the cryptex on the bed. "there's nothing my magnetism can do with this. We would have as much luck turning the letters with our hands, and it would be less exhausting to me."

Before Alice could answer, the door slid open, revealing a perplexed Helen Magnus who lifted and eyebrow and crossed her arms in front of her when she saw the two girls on Nikola's bed.

"I thought I heard voices coming from here." She began, trying not to smile as Sophie and Alice froze, not before trying to hide something behind their backs.

"Will you tell me what you're doing here or shall I have a guess?"

With more than two centuries behind her, Helen had mastered the skill to keep a straight face even when she was laughing on the inside. And seeing those two blush was something that definitely made her crack a smile. Even though Alice looked a lot like her mother, she had the exact same sheepish face Henry had when she reprimanded him. And Sophie… Well. Nevermind how different she was from her parents, she still had Nikola's attitude sometimes. And now was one of these times.

Seeing Sophie and Alice plot behind her back was very similar to seeing Nikola and Henry screw up in the lab, and some days, Helen thought she was surrounded with children. Which was somehow the case, considering the number of children engendered by her staff.

"We were bored." Sophie tried, clenching her teeth in a forced smile.

Helen tilted her head.

"You're supposed to be in class." She corrected.

"Ain't that the same thing?" Alice whispered only loud enough for her friend to hear, not daring to be disrespectful to the doc.

Helen huffed and closed her eyes to breathe.

"Girls… I know school is not challenging enough for you right now and I promise we'll find a solution as soon as possible. I'm working on it. But please be kind to Abby. She volunteered because she cares for you." She explained.

The two girls exchanged a guilty look and got up from the bed, looking defeated.

"Recess is over. Come on, shoo." Helen said, getting aside to let them out the door.

Noticing Sophie had her hands clasped behind her back though, she extended a hand both to stop her and retreat whatever her daughter had taken from the room, earning a disappointed look from the child who deposited the cryptex into Helen's palm with a sigh.

"For the record, we've tried the words "pigeon" and "Sophie"." She said, her grey stare full of the knowledge that her mother would of course try to open the brass case as well.

Helen couldn't help a side smile of amusement at how well Sophie knew her already. And before she could retort, the girls were out of the room and running to class, leaving her standing just inside of Nikola's room, his – presumably – mot treasured belonging in the palm of her hand.

Of course, Helen had no wish to invade Nikola's privacy. Still, she was curious. Not curious as to discover what Nikola would go to this length to hide, but rather as to what password he would choose for a cryptex.

She bit her lower lip, trying to repress the need to fidget with the artefact. She would simply put it back into his nightstand and go back to her day and forget all about this…

"Ugh" she groaned, not able to fight against her instinct that told her that she had to solve every puzzle that was presented to her on such a silver platter.

"Alright, one single try won't change the face of the earth." She decided.

Turning the object in her hands, she analyzed the situation. Nikola was far too careful to choose the name of somebody he loved – just in case somebody would realize he actually had a heart – or of something he liked. It was common sense.

A mischievous smile lit up her face and she shook her head lightly. No. That would be… Somehow typically Nikola. She thought.

She shrugged and set to turn the rings around the cryptex. Maybe, just maybe, Nikola would think that choosing something or someone he hated as a password was very clever. This would be far too easy, but still, she had to try. Only for the fun of it.

E, D, I, S, O, N…

The cryptex emitted a loud click and the lock disengaged, to Helen's utmost surprise. She snorted, letting amusement get the best of her for a split second. But when she realized she had unwittingly unlocked what Nikola obviously wanted to keep a secret, she froze. Nikola was, as everyone sharing his living space knew, not the kind of man to hide something he was proud of. Whatever the jiggling metallic item inside of the box was, there was a good chance Helen would not like it.

She frowned, her nose crinkling in the process. A few years back, she would not have hesitated to peek, judging that whatever Nikola kept hidden was necessarily dangerous or unethical. But they had been living together, raising their daughter together, and yes, also sleeping together increasingly often for the best part of ten years now and Nikola had not given her any reason to doubt his motives. He was still very focused on his own research, but she supported that. Their pillow talks included listening to his rambling about new inventions for hours at a time.

For a short while, she wondered whether she would be able to sleep without knowing what was in that cryptex.

At last, finding out that she didn't care one-bit what Nikola could be hiding in there, she reengaged the lock and turned the brass rings haphazardly, securing her very own vampire's secret safely inside of its box, to be forever forgotten. At least by herself.

Two days later:

Helen did not raise her head from her screen until she felt her desk vibrate under the weight of a brass cylinder being deposited on next to her hand.

"You haven't opened it." Nikola said blankly.

He knew. He had checked the recording from the hallway camera as soon as he had seen his cryptex had been moved. Luckily for his sanity, Helen had stood in the doorway when she had recovered the cylinder from Sophie, and she had stayed in the angle of the frame all the while.

He was still buzzing from the discovery that she seemed to trust him enough not to invade his privacy. Seeing everything unfold on the screen, something had clicked deep inside of him, prompting him to share his dirty secret with her.

Helen was not surprised that he knew about her little misadventure. However, she frowned at seeing the object on her desk.

"You don't have to show me what's inside, Nikola." She declared, flashing him a reassuring smile.

He pushed the box to roll it closer to her hand with a side smile.

"It's a gift. For you."

Helen raised an eyebrow, studying his face. He seemed on edge, and it was a rare thing for him to produce sentences that ran less than ten words. She cleared her throat and licked her lower lip, absentmindedly. There was something about his demeanor that sent alarms blaring in her brain. He was only this stressed when it came to romantic feelings, she realized.

She stared at the cryptex for a few seconds, as if trying to judge whether it could burn her fingers or not.

"Come on, you already know the password. Congratulations, by the way." Nikola encouraged, balancing his weight from one foot to the other like a child waiting to see if his gift was good.

There was a sparkle of amusement in her eyes at that, and she decided that the faster they got other with it the faster it would clear the air. So, she took the cryptex and reclined in her chair, drowning her gaze in his with a cheeky smile.

"My memory's playing tricks on me, I'm afraid. What was it again?" she teased, earning him a disapproving look.

She turned the brass rings once again and the click sounded vaguely decisive, only thickening the air in the room.

She disengaged the lock, placed it carefully on her desk and tipped the case to let its content fall in the palm of her hand.

Nikola had drawn closer to her. He now stood with his body right against the edge of the desk, his hands planted on the hard wood to get his face close to Helen's so as not to miss her reaction. When he realized he was holding his breath, he filled his lungs fully, only to fail at letting out the air again.

No one could blame him, he had waited well over a century for this moment, which he had long thought would never come at all.

When Helen realized what she had in her hand, she held her breath too.

She had never even once thought Nikola would propose to her. They had brushed the subject aside when she had discovered she was pregnant with Sophie. She had clearly stated that she needed more than empty promises, and that legally they were both dead and administratively not able to marry.

But never had she thought the idea had crossed Tesla's mind way before that. Way, way, way before that, she realized when she took in the antique looking gold ring.

It was simple enough, for a Victorian engagement jewel. A finely carved ring with a single deep-red oval garnet set in the middle of it. It was very reminiscent of how they had met, the red dress she had worn that day and the autumnal light. The ring suited them. Big but not conspicuous. Elegant but in a simple, easy kind of way.

Her absence of reaction made Nikola very aware of his position, and he felt the need to jump in.

"It doesn't have to mean anything." He blurted out.

His intervention got Helen out of her trance, and she shook her head, smiling faintly.

Finding his gaze, she closed her fingers around the precious gift Nikola had treasured for so long.

"But it does, Nikola." She whispered.

He searched her face, trying to understand what she was trying to say, but finding no sign of refusal, his eyes rounded in hope, making Helen's eyes twinkle with mirth.

"It means you trust me with your feelings." She clarified.

She intentionally left out the part where she understood he was very much committed to their relationship and had been for a certain time, but he got that from the twitch of the corner of her mouth.

He shrugged.

"It seems you do too." He retorted, not shying away from her meaningful gaze.

At that, he saw tenderness wash over her face, and a fond smile spread on her lips.

"I do." She confirmed.

He had been so focused on her face that he had not noticed she had slid the ring on her finger – it fit perfectly, he had made quite sure of it. But when Helen cupped his jaw, the cold bite of the gold made his gut clench in disbelief and he crushed his lips against hers, desperate to make this dream last longer.

The kiss was sweet and loving, and when they parted lips to breathe again, Nikola found some mischief in Helen's smile.

"You realize I'm going to make you wear a ring too?" she asked.

He grinned. Of course, she would. There was no way she would go around with a symbol of how she belonged to him if it was not reciprocal.

"Yellow compliments my skin. Do your best, make it dramatic. I want people to stare and be green with envy." He purred in her ear.

Even lost in the feeling of the goosebumps trailing her neck, Helen could not help a small snort.

"I honestly didn't know you could be so snobbish." She whispered, her shaky voice grazing his jawbone.

At that, he took a step back, raising his arms theatrically and he sighed.

"I prefer to say I have good tastes. And then, you want the ring to match up to the wife it represents."

Helen did nothing to hide how his flattery affected her, blushing slightly while rolling her eyes.

"Now," she said, fiddling her new ring absentmindedly "will you let me finish what I was doing before you stormed in?"

He wiggled his eyebrows and circled the desk to breech the distance between them.

"My my Mrs. Tesla..." He began.

"Or Mr. Magnus..." She retorted, raising her eyebrow.

"Whatever," he answered, brushing the subject aside in the same way they had done countless times about Sophie's last name. "Aren't we supposed to consummate?" He asked, looking at her with a suggestive look that did nothing to get Helen to regain her focus.

In an attempt to use his charms, he placed his hands on her armrests, effectively blocking her between his arms.

"You forget I still haven't put a ring on it." She chided, inching her face closer to his and caressing his ring finger with the tip of her index.

That did nothing to deter him. Quite the contrary. A wolfish grin appeared on his face.

"I could consummate you now and you could consumate me once you've got a ring." He suggested, his gaze setting her lower abdomen on fire.

She had to stop this now or she realized there was no way she could finish her task that day. So she placed her hand on Nikola's chest and caved in.

"I'll be in your room at 8. Happy?"

He grinned and took the hand resting on his heart to place a soft kiss to her palm.

"Don't be late, wife." He concluded, obviously quite proud of himself, leaving the room swiftly before she could correct his vocabulary.

Once the door had closed itself, Helen snorted. The snort turned into a peal of laughter. Two days ago with Nikola's cryptex in the palm of her hand, she never would have thought she would soon think of herself as Dr. Magnus-Tesla. Although... She shook her head. It was only a ring. They were not married or anything...

"Blimey." She sighed.

Of course they were a little bit married, in the secrecy of their hearts.