CAL STOOD ON THE edge of the cliff. His shoes displaced a few pebbles that tumbled soundlessly into the void below him and he looked down, immediately wishing he hadn't as a surge of vertigo swamped him. Waves smashed against the bottom of the cliffs, and the vibrations carried through the stone to his trembling legs. Salty air pummelled him where he stood on the edge.

"Jump!" screamed Helena over the noise. "Just do it."

She hung a few meters away, the wings of her parasuit fluttering in the updraft. Deftly she controlled her position with quick adjustments of her arms and legs. She grinned at Cal.

Do you trust me? Helena's voice whispered into his mind and he nodded at her.

Then jump. I will be here. You cannot hurt yourself seriously.

It's the 'seriously' bit that worries me. He threw back at her.

"Just jump you numpty!" she screamed at him again. Gathering his failing willpower, he leapt into the sky.

~~~

A few minutes later, he lay on his back in the rabbit cropped grass at the top of the cliff. Helena ran around him in circles, whooping with delight. "You did it, you actually did it!"

He propped himself up on one elbow, and smiled shyly. "I did, didn't I? I'm not sure I enjoyed it, but I did do it."

Laughing, she threw herself on the ground next to him and punched him in the shoulder. "Well done, Cal. You've got to remember it's all simulated though. There's no way you could've fallen."

"I know, but it seems real."

"It's meant to, that's why people spend so long plugged in."

"Well, we ought to get started on those calculations for Dr Takei."

"Party pooper," she pouted.

He stood and proffered a hand, which she took, and hauled her to her feet. "Thank you for making me do that Hel, you always seem to know when I need to do something daft."

"That's what friends are for. After fifteen years together on The Mind's mathematics programme, I should know when you need a kick in the seat of your adventure." She grinned at him again, and brushed the hair away from his eyes with one hand. "Besides, tomorrow we're going to do it over a live volcano. You keep saying you'd like to know more about geology."

Shaking his head at her as she laughed at him, he focussed inwards.

Mind?

- Yes Cal.

Run program Beta 3 please.

- On its way Cal, prepare for transition.

"Party pooper," said Helena again as the scene around them dissolved. Their parasuits disappeared leaving them both in simple jumpsuits. Surrounding them was a room covered in blackboards, various mathematical formulae scrawled on the surfaces.

"Hang on, one minor improvement." Helena cocked her head to one side, as she always did when she communicated with the Mind. Then she looked up, prompting Cal to do the same.

The ceiling disappeared as they watched, replaced by a myriad stars.

"Nice," murmured Cal approvingly. "The skies above Australia?"

"Yes. I've always loved the Southern Cross. We can do the Northern Lights when we've finished perhaps."

She sighed. "It's a shame we can't see them."

"We can see them there," he said gesturing at the sky above their heads.

"No, I mean really see them. Go outside for real, lie on the grass and stare into infinity."

"There is no grass Helena."

"I know. I just wish sometimes we could actually experience what our ancestors did."

Cal took her hand and placed a piece of chalk into it. "Come on, let's not dwell on that, we've got work to do."

She looked at the boards and picked out the last equation she'd worked on, adding a couple of minor corrections. "Last one to get the answer is making the sandwiches."

For the next few hours the two of them covered the chalkboards with complex equations, a sea of algorithms and formulae pinned to the wall in chalk as they worked through various concepts.

~~~

The boards had been filled, wiped and filled again in a frenzy of abstract mathematical thought. The Mind had recorded all the changes and alterations as they went so they could work through them in their pods over the following days.

Cal sighed and stepped back from the chalk board, a long series of equations terminating in a single, simple, formula.

"Can it be that easy?" he said after a moment.

"Why not?" replied Helena. "Sometimes things simply boil down to whether it's right or wrong, black or white, light or dark. Just because something turns out to be simple, doesn't mean there's not something incredibly complex leading up to it. Sometimes you overcomplicate things, Cal."

She walked away from him and lay down on a table looking up at the starry sky above their work area. "Twinkle twinkle little star," she murmured.

"How I wonder when you're going to go supernova?" Cal joined her, lying next to her on the table. Staring upwards, he winced as she punched him on the arm again.

"I'm sure that's child brutality you know," he said, grinning.

"You're not a child, you're sixteen. Besides, I'm younger than you, so it doesn't count."

Still grinning, he sat up, staring back at the chalkboard again, his brain working furiously as he ran through the calculations leading to the last formulae.

"Let it go Cal, we've done enough for today."

"But I don't think it's quite finished. I think Takei will be disappointed in me for leaving it there."

She looked puzzled for a moment. "You really have no idea how special your brain is, do you?"

"I'm not special. I'm just me. You're the one who does all the crazy stuff." He gestured at one of the blackboards to his left. "I'd never have thought to add in that section, but you just did it for a laugh and made it work. It's completely illogical, but you made it work."

She sat on the table next to him. "Logic can't do everything, Cal. Sometimes you have to just let go and trust your instincts."

He smiled at her. "Jumping off a mathematical cliff?"

"Absolutely, but remember, you're the one who seems to be able to communicate with or without Mind. I can't do that."

"Not yet you can't, but I think we could work on that."

"Enough for today, eh?" she said and held out her hand. "Come on, let's get something to eat. I think Dr T will be happy enough with all this for now."

She cocked her head.

Mind, disconnect.

~~~

Cal opened his eyes to the smiling face of Dr Takei greeting him in a sterile white room. Helena, sitting in the chair next to him, spoke first.

"Hi Doc, got any food? I'm starving."

"Honestly, teenagers, all you ever think of is your stomach." The Doctor grinned and waved at a nearby table with a couple of trays on it. "Have I ever failed you, Helena?"

"No Doc, you never have. Thank you."

"My pleasure. I think there are some aubergine fritters there somewhere, I know you like them."

There was a muffled sound of appreciation from the far side of the room as Helena filled her face. Cal stood, moving to join her. "Mmm, Cal, you need to try these."

"I see you've made good progress with the Jaken paradox," intervened Dr Takei. "You two are a good team." He changed the subject. "And did you enjoy your cliff diving, Cal?"

"It was okay," said Cal cautiously.

"It was tame," replied Helena. "The systems are too limited. There's no risk, and you don't get the full sensory input like you get here for example. This," she waved a sandwich, "would taste awful on the Mindscape, just as things like smell are limited. Sound is easy, but this," she gestured at the implant behind her ear, "should be capable of a much more full experience. It's great for mucking about with bits of chalk and projecting nice things to look at, but it's just not 'real' enough. You'd think with all the technology we have around that we'd be able to Link better."

"Point taken," said Takei with a gentle smile. "So, if I could offer you a more submersive experience you'd be interested in trying it?"

"Hell yeah," said Helena, her eyes shining in excitement.

Cal poked at a suspiciously hot looking pepper on a pizza, prompting a tutting noise from Helena. "Well, I'd like to know a bit more before we..."

"Oh stop being a stick in the mud Cal, where's your sense of adventure?"

"Well, I guess it wouldn't hurt."

"That's my boy," she said. "Is it ready to go Doc? Can we try it now?"

"Strangely enough, yes, it is. I thought I'd get it ready now as I know you tend to have little or no patience, Helena."

Cal laughed, catching a glare from his friend, and shrugged his agreement. "Okay Doc, lead on. Let's see what all the excitement is about."

~~~

Cal stood, fidgeting uncomfortably in the skin-tight suit Takei had given him. Helena appeared from a side door, similarly clad, and grinning from ear to ear. Two coffin shaped objects were the focal point of the room in which they now found themselves, the standard issue white walls of the City stark in their cleanliness.

"Ah Helena, good," said Takei striding into the room. "Now, these things here are complete immersion booths. The suits you're wearing are advanced prototypes. They contain micro circuitry that connects with the biogel in the booths, and your own implants. It should render a near perfect replication of 'real' life."

"Near perfect?" asked Cal.

"Nothing we can simulate can perfectly match humankind's innate ability to read other humans. There are still things we don't fully understand about the human brain. But this is as close as we can get at the moment.

"Are you sure it's safe Doc?"

Helena blew out an exasperated sigh. "Oh for pity's sake. Come on Cal, don't you want to try something new. Be the first?"

"Well yes, but..."

"Come on then."

Cal sighed, and opened the lid to his booth.

~~~

There had been a moment of panic as the lid had closed, but he suppressed it and lay on the padded surface of the pod. He could see and hear nothing. He poked himself in the leg just to make sure he was still there.

Ready?

Helena's mind touched his and he smiled.

As long as you're there, I'll be ready.

I'll always be there for you Cal, you know that. See you in a moment...

The pod began to fill with the biogel Takei had briefed them about, and Cal felt the body temperature goop rising up the inside of the pod. As it reached his face, he very deliberately opened his mouth and, subsuming the reflex to hold his breath, determinedly pulled a mouthful of the liquid into his lungs. His body reacted exactly as Takei had said it would, choking and trying to cough out the liquid, but the oxygen rich mixture took only seconds to settle in his lungs. Panic gave over to relaxation and he was completely submerged, lying suspended in the biogel.

He opened his eyes, and the shifting colours of the insertion routine swirled into his vision.

Takei's voice whispered into his head. All going well Cal. Insertion continuing. Soon you will find yourself in a very different place.

Darkness turned to light, and the Mindscape expanded. Lines of equipotential grew, shifted, and morphed, and Cal found himself standing on an endless plain of green and black. Lines stretched, built and formed into shapes. Colour was added, and abruptly he was standing on rolling green hills, grass moving gently in an invisible breeze. Scents of clean air and ozone hit him, and he breathed deeply, smiling as the unusual smells of nature filled his senses.

Helena, are you seeing this?

I'm not sure what you're seeing Cal, but I'm subsumed by stars. I can see everything. There's just so much to see, it's an infinity of light and dark. It's just so beautiful. I can feel the stars Cal. I can feel them calling to me. I wish you were here with me. They're calling to me Cal. There's so much more to the universe than what we know in the City. We need to see the stars Cal, we...

Helena?

Cal, something's wrong. Everything's gone dark. I'm not sure what's going on. I'll contact Mind and disengage. I'll see you in a moment Cal. Enjoy yourself. Go find a cliff: jump.

The grass faded as Cal lost interest, the waving fronds disintegrating.

Mind, disengage. He commanded. Mind? Dr Takei? Is there anyone there?

Disengage.

Disengage.

~~~

The face of Dr Takei swam into clarity as the gel slid from his face. Cal struggled from the pod, his lungs rejecting the oxygen rich gel as he emerged coughing from his submersion. He coughed up the remainder of the gel and spluttered out "Helena."

There was only one pod in the room.

"Doc, where's Helena?"

Takei placed his hands on Cal's shoulders and sat him down on the edge of the pod. "I'm sorry Cal, she didn't make it..."

Cal stared at him blankly, his brain struggling to comprehend the Doctor's words as gel splatted to the floor.

"There was a malfunction. An electrical charge built up in the gel in her pod. We noticed her brain function decreasing but thought she'd been overwhelmed by sensory overload, which can happen sometimes when someone first uses the Pod. But it was the charge leaking from the gel into her brain. We had to knock you out and slowly disengage you which is why you were under for a little longer: long enough to allow us to remove her.

"I'm sorry Cal, truly I am. I know she was your friend and a truly remarkable girl."

"She's gone?" he said. "But that's impossible." He bowed his head and cried, the Doctor's hand once more resting helplessly on one shoulder in comfort.

Helena, my friend. I hope you reach the stars.

Numbly he allowed the doctor to shepherd him into the changing room and he showered away the gel and tears.

He noticed his watch as he reached for his belongings. The archaic device was a foible of his, a gift from his old mathematics professor. Its chunky design and small screen had delighted him. And, after much tinkering, he'd managed to patch it into some of the City's systems so Helena and his few friends could send him messages.

Helena's face blinked at him from the screen. The timestamp was from one minute ago. His mouth went dry as he read the simple message.

"Help Me."

~~

Music - Knot in my Heart by The Zolas