DISCLAIMER: It was, more or less, based on the storyline of the episode 'Utopia'. Obviously, I'm not claiming ownership over the lines and actions written in the script.

[Approximately two years before, at Torchwood Three, late night]
Adriana stood on the balcony, smoking. Her head rose to the dark night sky, and a longing crawled up under her skin. Space - such a glorious mechanism, operating with beauty. Her daydreams never excluded passing by the planets of the Solar System only to jump into deep space to explore the galaxies those science fiction novels wrote about.
And next to her, there he was: the man who seen it himself, not even born in any century close to today. Captain Jack Harkness.
He also lifted a cigarette to his mouth, inhaling the thick smoke before speaking. 'Adriana. There's something else you should know about. There was this man I traveled with for a while, his name was...'

'DOCTOR!' Jack shouted from the bottom of his lungs and Adriana found it hard to keep up with his pace. The blue police box was just about to dematerialize when the Captain desperately threw himself on the departing ship, and the girl followed him like a fool. The surroundings changed suddenly, and they were clinging to the wooden box with all their strenght, altough Ada's arms were all too short to hug it around like the man did. Jack pulled her closer, squeezing her between the Tardis and himself.
'Hold onto me!' he instructed over the strong wind.
'I don't think that's a good idea.' she looked up to him while grabbing the doorhandle with both hands.
'I believe it is.' he grinned at the thought of her snuggling up to him, and the girl knew him all to well. However, deep down, she was still amazed and grateful to him. Without Jack shielding her she would be dead by now.

Just as she finished that thought, they landed and the captain fell to the ground. Ada shifted to him like a flash; even though she experienced his immortality first hand, it was still a strange concept she yet failed to get used to. She was disturbed as the TT capsule's door flung open, and two figures stepped outside.

'Oh my god!' the black girl shouted. 'Let me there, I'm a doctor.' she pushed Adriana aside to check the lying man's pulse and heatbeat. Ada glanced at the tall man dressed in a brown, pinstriped suit with an annoyed expression on her face, as if they'd share an inside joke, and the latter returned it.
'There's no heartbeat, no nothing!' the girl examined Jack further, when he came back to life out of the blue, gripping her slim arms. It took some moments to regain consciousness.
'Captain Jack Harkness. And who are you?' almost every word he spoke was flirting, even hanging just above death, but it was seemingly enough to charm the lady and forget the uncomprehensiveness of the situation.
'Matha Jones' she responded.
'Nice to meet you Matha Jones-'
'Oh, don't start!' the man demanded to put an end to their interlude, and Adriana found herself being overly thankful for that. Jack's affairs always brought a smile on her face, but enough is enough. She stepped forward, back to her captain to help him up.
'I was just saying hello!' he protested. 'Speaking of hellos, nice to meet you, Doc. This is Adriana Leighton, my friend.'

The Doctor examined the girl from head to toe. Her long, blonde hair and brown eyes sent a shiver down his spine, but it did not stop him from noticing the pair of black Converse. The sneakers got his attention, and didn't hesitate to point it out. 'Nice shoes.'
She curtsied him jokingly. 'Thanks. Yours are pretty cool, too.' then, she extended her small hand to him. 'Adriana Leighton. I'm happy to finally get to know you, Doctor.'
They shook hands, altough the Doctor observed her with distrust.
'Do you know each other?' Martha inquired, eyes bouncing from one of them to the other like a ball.
'Traveled with the Captain for a while...' the Doctor explained.
'You abandoned me.' he intercepted abruptly. 'Anyway, just gotta ask... On the list of the dead of the Battle of Canary Wharf... There's the name of Rose Tyler...'
'Oh, no, she's alive!' the Doctor chimed. '...And Mickey and her mother.'

[July, two years ago]
Jack landed the helicopter on the rooftop of Torchwood One and he stopped the engines. As they were pulling of the headsets - unnecessarily big ones as Adriana noted - the captain turned to the backseats to pull out a carefully arranged bouquet of red roses. He was dressed surprisingly neat, almost making her uncomfortable for opting for such a casual outfit; nevertheless, he did not reveal the purpose of their trip to London. Ada couldn't supress a teasing question: 'Should I be jealous?'
'No.' Jack snapped without even looking at her. Her eyes darted to the ground and strolled quietly beside him fom that point on.

Only when she stood before the immense marble memorial is when it hit her: it was the anniversary of the Battle of Canary Wharf, though it still puzzled her why did Jack reacted so sensitively. He placed the bouquet under the wall tributed to those who lost their lives due to the bloodshed of the Daleks and Cybermen.
'I'm sorry I brought you here, but I haven't had the courage up until now.' he explained himself after long moments of silence. 'A friend of mine, Rose Tyler...' his voice grew weak, so he paused and Adriana turned to him to hug him tightly. The captain bowed down a bit to put his arms around her and she gently stroke through his hair.

'She was sweet and brave. Haven't seen her since I first died then bounced back to life.' he countinued, turning back to the memorial. 'We met in London, during the II World War. She hanged from a barrage ballon and I saved her from falling, but when I figured she must be from the future along with her companion, I tried to sell them the empty Chula ambulance. I thought they must be Time Agents like I was...'
'Sounds more like you were a conman.' she insterted cheekily.
'Hey, trying to relive some memories here!' the man appeared insulted. 'Anyway, this is how I met the Doctor. Quite a twistful adventure; I almost died at the end...' the captain carried on with the tangle and Adriana's eyes twinkled in awe, as they left the base to wonder around the streets of London.

They were walking down a dark meadow; in fact, everything was unnervingly dark, but noone seemed to take note of it. The vegetation was poor, struggling, and one couldn't quite put a finger on it if it was the soil or the lack of light. Or too much of it.
'But I had this - it's called the vortex manipulator, he's not the only one, who can time travel...' Harkness began to brag the way he always does, and the blonde girl on his right side rolled her eyes. She expected it coming, Jack and his roistering, but she had to admit, he dazzled her the same. He deserved some admiration, afterall.
'Excuse me, that is not time travel!' the Time Lord pointed at the device. 'Like, I got a sports car and you got a space hopper.'
The Doctor's comeback made her giggle; Martha, on the other hand, wasn't so shy to insert her own: 'Oho, boys and their toys!'
'Okay, so I bounced.' the captain let it go soon and followed with how they ended up here, beside the Doctor.
'But, that makes you more than a hundred years old!' the black girl was surprised hearing that the good looking man beared through more than a century. It's so unbelievabe at first...
'And looking good, don't you think?'
'He has quite a story to tell.' Ada added slyly, but the captain carried on with his own tales before she could insert those nasty parts that wouldn't impress dark haired girl walking by his side. Adriana rather fixed her eyes on the Doctor, scanning this peculiar man she was so curious about. Space and time travel... She only realized then she was just on her first of such journeys (and maybe the last, a venomous voice whispered), which made her stomach cramp with butterflies.
'So, I've gone to the time rift, based myself there, cause I knew you'd have to refuel... That's where I met this lovely lady.' Jack hugged the short girl to his side. 'She helped me with my search for you, and the only person I could confide.'
'The only person crazy enough to trust him.' Adriana clarified.
'But the thing is, how come you left him behind, Doctor?' came the interrogation from Martha.
The Doctor only muttered the explanation. 'I was busy.'
'Is that what happens tho, seriously? You just get bored of us one day and dissapear.'
'Not if you're blonde.' Jack teased him then glanced over to Adriana. 'You have a safe bet with him.'
'We are right at the end of the Universe, and you're too busy... Blogging!' the Time Lord craved the change of topic so much by then. He strolled ahead, and Ada intended to catch up, extending of her steps.
'Are we? Really at the end of the Universe?'
'100 trillion years into the future, yes. Quite a drastic one for a first travel.' he glanced down her with eyebrows raised.
She studies the surroundings. 'Not how I'd imagine the end of it all...'
'Well, there aren't fanfares for sure... Even the stars died out, that's why it is so dark.'

'Look! It's a city.' Martha yelled, finger pointing downhill.
'Or a hive. Or a nest...'
'It's beautiful...' Adriana breathed.
'Only lifeless.' the Time Lord judged. Once, those pathways and windowed living spaces streching far below their feet flourished with creatures going on with their daily chores, and now it was gone. By the speech of the Doctor, all of it: civilizations, humans, the stars... Everything was eaten up by time. A hollow took its place in the blond girl's heart, but she couldn't be swallowed up by it to much.
'Well, he's not doin' too bad.' it was Jack's voice that yanked her back to reality. A tiny figure ran just below them, apparently being chased by a suspicious group growling loudly.
'That looks like a hunt. Come on!' the smartly dressed man ran straight into trouble.
Adriana barely heared the captain's exclamation ('Oh, how I missed this...'), as she was too occupied with rummaging around in her backpack for a proper gun. By the time they surrounded the man as a shield, she was ready to aim.
'You two!' the Time Lord scolded her and Jack, who, too, had his pistol up. 'Don't you dare.'
Jack fired into the air in hopes of scaring the wicked looking humanoids off, whereas the girl lowered her gun with a sigh. She strategized how easily she could have just shot a bullet into their knees to slow them down without taking their life, but it was useless to contemplate on it anyway. More roaring creatures came from the direction of the TARDIS, so that option was closed.
'...There's a silo nearby. If we go there, we would be safe!' the unknown man offered, so the Doctor surveyed them: 'Silo?'
'Just go, go, go!' Ada hurried them, and they went after the one who suggested. Martha fell behind, and recognizing it the other girl grasped her, forcing her to run faster.

'Show me your teeth, show me your teeth!' was what greeted them, and they obeyed, showing off the pearly whites which gained them all access into the defended area. The guards assured those predatory creatures would not pass the gates, yet they remained patiently outside, hungry for human flesh. They hissed behind them, even as the time-travelling gang approached the inside of the construction.
'Well...' Jack panted as his blue eyes fell to the long haired girl, huffing similarly. 'Doctor - check, aliens - check, running - check.'
'Welcome on board.' The Doctor flashed a smile.