Cheating. That's what his plan was. He cheated. Flashed to the future. That's very him.
They never get it! You're part of events! By jumping in and out you're only making things a zillion times more complicated! There's temporal doubles, paradoxes and zigzagging timelines that would make Belgium implode.
The universe doesn't exist to be messed around with just like Towers weren't made to fly through space. If you mess with its foundations it's inevitable it'll fall apart.
Energy can be neither created or destroyed. The pieces are still there, it's just the arrangement is gone. Who knows what it'll turn into next when you start fiddling with time and space?
It's not just mankind you're changing. Ripples of the event grow outward and turn into waves, which in turn become a tsunami. That's why some things are fixed! They are the foundations of history and if you pull the metaphorical building block out from under the tower it will collapse.
How many times must I say it? It was a terrible idea and you thought it just might work.
You probably felt the after-effects of the antics of his time vortex manipulator all scrambling your insides. That's what you get for space hopping around the universe. Some might say you deserve it. It really is bad for you.
Jack asked you for a random year in the future (anything at all) and the first date that popped into your head was your birthday. A rainy day in June in the year 1989. One hundred years after the Eiffel Tower had been stolen.
One hundred years after all of this had taken place and the world was left as if nothing had happened. Except appearances can be deceiving.
"There're cars!" you noticed in the distance. "We're in the future!"
"June 1989," Jack said. "Your past. It could be the eleventh but I might be off by a few days. Or months."
A colourful new world. You couldn't help but imagine everything had just been a dream. A feeling you'd know quite well. But you weren't sure who abandoned who this time.
You were starting to doubt whether taking the arm of this stranger had been such a good idea.
"Great. Another time-traveller," you said folding your arms together to shield yourself from the cold.
Jack checked his wrist device. Rain drenched and drowned all speech and you followed Jack underneath one of the trees in the park to hide from the rain.
Jack had to correct himself: "No, it's not June. It's August," he said. "It should be here!"
It hadn't gone quite as he had expected.
"We've just traveled a hundred years into the future. Why?" you asked him.
Jack evaded the question. He was busy scanning for something. Something quite important.
"D'you notice anything different? Anything unusual?" he asked you.
"Well, there's you," you spoke dryly and Jack grinned.
"Can't say I'm not unusual. But that wasn't my point. Look around."
You played along. It didn't seem very unusual to you. In fact, to you it seemed like an ordinary park.
"Where are we? Are we in England? Oh, God, I'm barely a month old. This is so weird."
Then suddenly it started to dawn on you. Fragments of your mind pieced together to form an image. I know just the feeling.
"This is Paris. We're still in Paris. We haven't moved," you finally realized and you looked up. "The Tower. The Eiffel Tower. It's gone!"
Imagine a world without the Eiffel Tower. It's just like this one only without the Tower. How much would it have changed, you think? What impact would its absence have had?
It's almost iconic now, a landmark of France, ingrained into the popular subconscious through movies and postcards and tourism. But take it away and the world just adapts around it. Time just works that way. It's the universe plus one or minus one. The universe does not care. It's indifferent. It merely adapts.
Now imagine a universe without mankind. It could happen. Time could be rewritten.
"The Eiffel Tower was stolen a century ago," you said to Jack. "The Doctor had a hundred years to restore it but he didn't. It's not there so he must've failed. We must've failed."
"Don't say that," Jack stepped in. "There's gotta be some way to get him back."
"Look at it! It didn't happen!"
"But it can happen!" Jack spoke. "We can still do it! We can change time!"
More bad news. "It's still there. You can see it in the air. It's the crack. It's here too. One hundred years into the future. The year that I was born. It's exactly the same as it was in the past."
"The Doctor needs our help," Jack said. "And I need his."
"Who are you?"
"Call me Jack," he said.
"Is that your real name?"
"Oh," Jack beamed. "I bet he likes you."
"Nice way to dodge the question there... Jack." you said and you nestled in the dirt where he was digging right atop these roots of a horse chestnut tree. There was less rain, more dripping and a whole lot of shivering, but that didn't stop you looking.
"American, right? Too bad. The French greet each other with four kisses."
"Where I come from it's eight," Jack teased.
"What are you doing?" you asked.
"I used to be a Time Agent," he said in between gasps of breath. His blackened hands were digging deep into the dirt. "There's tricks we used in bad situations. A lot like this. You won't believe the ways we used to manipulate time to our own advantage. For instance."
While he was pulling a massive metal chest from the soil you were racking your brain to explain how he'd done it. Magicians rarely reveal their secrets but I think if you buy him a drink you're off to a good start.
Jack brushed the dirt off the lid of the chest to read its inscription with a final sigh.
"We used to go back in time and hide weapons or explosives in places where we knew we would need them in the future."
"That doesn't make sense," you said. "You can't do something before you've done it."
"You'll be amazed at the things we get away with," Jack said. "It's all temporal mechanics. Don't think too much about it. All it does is give you headaches."
Jack clasped the lock of the chest and thought of a number in his mind completely at random. Let's say, 5556. Then he entered that number, and lo and behold, the chest opened.
"Oh boy," Jack said.
You jumped when Jack pulled out a semi automatic handgun, three grenades and a bucketload of ammunition.
"What is that?"
"Necessary evil. Sometimes you have to fight fire with fire," Jack said and he stuffed the rest of the contents of the chest down the pockets of his coat. "God, I love time-travel."
He shut the chest and didn't even bother to bury or dispose of it again.
"That thing's here," you said. "The crack. A hundred years into the future."
You're missing the bigger picture. It's not just here. It's everywhere. Every time, every place. Every Paris. Past, present and future.
"Time's in flux," Jack explained. "Everything we do today will have consequences."
You weren't even listening. You were watching him brush his hands clean. There was this sudden realization within you that you weren't scared when you should have been.
The world was coming to an end and all you could think of was my future. All the adventures I would still have with River. All those things that had already happened and would happen again, except now they would never happen.
You realized that all this time you were thinking of my future and not your own. It was like there was this veil that had been put between you and your future. You used to know what it was, you used to fear it and wonder, but what happened to your future now? All you're left with then was this aching feeling you were supposed to be somewhere, but you couldn't remember where. Somewhere important.
I'm right, aren't I? You don't have to say anything.
Like a dream half remembered in the morning dawn in that fuzzy state between sleep and waking up. If only you could remember him.
The present suits you, Amy Pond.
But if there's one thing I've learned from all my travels is that no matter how fast or far you run the imperfect past and future perfect will catch up with you in the end. Like a deadline or an ex-wife.
Past and future times were about to come crashing down around you. And sometimes you don't have a choice but to strap in for the ride. That's what I always do.
The clock was still ticking. Time was still running out everywhere, every time. But 1889 was key. You had to go back.
"Ready to save the world?" Jack asked.
"Sure," you said charmed. "It's not like I've got anything better to do."
You took his hand in the rainswept green heart of Paris and just before you flashed back to 1889 you added: "I'm single, by the way."
You returned like you hadn't left at all. 1889 could've blinked and missed it.
Jack told his Torchwood colleagues the exact contents of that chest in the future, and ordered them to make sure it would be there for him to find in his past and their future.
It's simple, really. I don't know why anyone would find that complicated.