Authors Note: So let me explain how this story is going to work, before you start reading. Both Halo and Stargate exist in the same universe, but not in the same galaxy. Everything that happened in Halo including all the books and games happened in the Andromeda Galaxy, everything that happened in Stargate SG-1 happened in the Milky Way Galaxy, everything that will happen in Stargate Atlantis will happen in the Pegasus Galaxy with a little Halo mixed in with it. Most of the UNSC characters are made up, only one character is from the games. I don't own either franchises, they belong to both their respective companies.

Pegasus Galaxy

Outer edge

2555

In the vastness of space a 3.5 kilometer long ship dropped out of slipspace and began its journey to the closest plant in the system

UNSC

Praeter

Cryo Bays

The cryo bays on board the Praeter activated, releasing its occupants and one man stepped out stretching and giving out orders. The man then went to a pedestal that was glowing white light on it "Yelena report." said the man

Yelena appeared before the man, her appearance was that of a young woman with shoulder length red hair wearing black pants and a white sleeve shirt showing a bit of her cleavage "Morning Captain! You look as old as usual."

The Captain gave a stern look and while he tolerated Yelena's sarcastic and sometimes uncaring attitude, he still expected her to act with integrity when the time came to do so. "Have the crew get cleaned up and report to their stations on the double."

"Aye sir, shall I make coffee and eggs for the crew as well?" asked Yelena crossing her arms and leaning to her side a bit.

The Captain didn't respond and began dressing in his UNSC uniform showing off his Captains badge. "Make my coffee black, no sugar." Said the Captain as he makes his way to the bridge.

UNSC

Praeter

Bridge

On board the bridge were officers of the UNSC, men and women getting straight to work at their stations, getting the ship up to status.

The Captain of the ship came on the bridge, one officer notices this and yells "Captain on deck!"

All the men and women stop what they were doing and stood up saluting their Captain. The Captain looked at the men and women who were serving under him, he needed to make a good impression.

"Ladies and gentlemen." started the Captain looking at his diverse crew. "I know we're a long way from home and that most of you don't know why we're here, but I promise you that this mission of ours, High Command sent us on will be accomplished and we will return home to our families." said the captain as he reflects back on the meeting he had with high ranking officials of the UNSC.

Andromeda Galaxy

Erde-Tyrene

9 months ago

UNSC High Command

2555

2 years after the events of the Covenant war the UNSC was fast track at restoring to pre-war status and had made great discoveries in that time. The UNSC's flagship Infinity was finally finished, Forerunner artifacts were being discovered and studied. As for the ordinary citizens of the UETG, they were continuing life as always without any fear of alien threats, but while the people were aware of species of the Covenant, the UNSC were keeping the Flood a secret from the rest of the population to prevent a panic.

At High Command Lord Hood along with newly appointed head of ONI Serin Osman were seated at a table in a closed off room as to maintain secrecy waiting for an officer of the UNSC to come in.

After a while Captain Alton walked into the conference room, a man in his late 40s with grey hair, standing at a height of 6'1; he took a seat in front of the two most powerful people in the UNSC. As soon as he took a seat Admiral Hood greeted him "Welcome Captain! How are you feeling today?" asked Hood

"Fine sir! Though I am curious why I was called here." asked Alton as he was trying to calm his nerves when in the presence of a superior officer.

Hood and Osman looked at each other for a few seconds and back at the files they had laid on the table. "According to your service record, you've been in the Navy for over twenty years. starting out as an officer and slowly working your way up the chain of command to the position of Captain." said Osman looking at his record.

Alton nodded his head, surprised on why they were bringing up his service record. Osman Continued her evaluation on Alton "According to the files from superior officers, you've been given high praise for how you handled yourself when it came to engagements with the Covenant and from that you were promoted couple of times."

Hood then took over "Two years ago during the battle of Erde-Tyrene, you handle yourself well and directed your crew exactly like an officer should, and manage to damage a Covenant Corvette, with just a Frigate."

Alton remember the battle, and while it was risky, he managed to get good shots at the Corvette before it began heading to the surface of the planet "With all due respect sir, it was the men and women that served under me that deserves most of the credit, because without them, I would not have been able to succeed."

Hood nodded his head "True! But your valor and determination is what drew the crew to trusting you in taking on a ship three times your size, which is impressive."

Alton taken back by Hoods compliment, began to relax a little and felt good to hear that from an inspiring office of the UNSC. As Alton was feeling good about himself , Osman took over "Which is why your perfect for this mission."

Alton soon shook off his flattery and looked at Osman "What mission?" asked Alton

Osman began pressing buttons and the center of the table began glowing and soon a holographic image appeared. "Most of the UNSC personal don't know this as well as most of the Civilian government, as we don't want to cause a panic to the citizens of the UETG."

Alton began looking serious and listened intently what Hood and Osamn was about to say. Both Hood and Osman began debriefing on classified information, about the Flood and Halo's and how Erde-Tyrene was close to experiencing a flood outbreak on the planet.

Alton was looking at a flood form and the parasite that causes it all, as well as an image of Halo, he was speechless "I...I don't know what to say!" said Alton shocked at the revelation of something so grotesque, it was the stuff of nightmares.

"All of this is still classified and cannot be spoken outside this room, unless authorized too." Osman sternly said as ONI doesn't like information leaks.

"Why tell me all this then?" asked Alton irritated by Osman's cloak and dagger personality

Hood and Osman began going in detail about an ancient alien race called the Forerunners, who fought the Flood only to fail and create the Halo's as a last ditch effort to stop the spread.

"From what we have gather about the Forerunners and the Flood is that the Flood is an extragalactic parasite that came to our galaxy a hundred thousand years ago during the height of Forerunner civilization and fought a 300 year war." said Osman

"During the Covenant war we uncovered some Forerunner artifacts including the Halo's, and have made great advancement because of it, but also discovered dangerous things." said Hood

"The Flood?" asked Alton thinking of how horrible it would be to face one of those things all by yourself.

Hooded nodded his head "Currently we have peace with the Elites and their busy pushing the Brutes back to their Home world of Dosaic, which gives us time to rebuild our fleet and our colonies."

"Unfortunately that doesn't help our current predicament." said Osman pointing out the dangers of the Flood.

Alton shifted in his chair, trying to remain comfortable while listening intently "What do you mean?" asked Alton

The holographic image change to a planet "Couple months ago a team was searching for any Forerunner artifacts or facilities for us to study, we came across this facility and to say we struck gold was an understatement." said Osman. "In this facility we found out it was a place the Forerunners used to study the flood, but the real main objective of this facility was to locate the Flood's origins."

Alton began realizing what this meeting was about and this could be the biggest thing to happen to the UNSC since the discovery of Slipspace. Osman continued the report on the discovery, "The information contained in this facility was extensive, but we manage to find what they were researching and located the Floods origins"

"You mean to tell me you know where they came from?" asked Alton

Osman nodded her head and the holographic image changed to show an image of the galaxy. The image zoomed out and showed a number of galaxies clustered around together "This is the local group, our galaxy resides in." she said as the image highlighted their galaxy as the biggest one in the group. "And this is the galaxy the Forerunners believed to be where the Flood originated." said Osman as the image of a tiny galaxy illuminated to stand out from the rest.

"Scientist call this galaxy, galaxy 3P4-7, but the Forerunners call it Path Kethona, it's a satellite galaxy for the second biggest galaxy in the local group"

Alton could not believe what he was seeing and was amazed "This is all interesting Admiral, but what does this have to do with me?" asked Alton

Hood took the lead on this one "Right now we have peace, but that won't last forever and while the Covenant have been pushed back, the next encounter with aliens may just be hostile as the first encounter, the only difference is will be ready this time around."

"While were prepared to deal with the next alien encounter, we have little to no defense against the flood." said Osman "Currently what's left of the flood in this galaxy are contained in Forerunner facilities and can be easily disposed of, but we cannot have another incursion of the Flood into our galaxy where they could show up anywhere and we would have no warning of their arrival."

"This is where you, come in Captain!" said Hood

"Me?!" said Alton surprised by their choice

"Your record speaks for itself Captain, you bring that fire of leadership that makes people follow you to hell and back." said Hood "Which is why we want you to lead an expedition to this galaxy locate the origin of the Flood and destroy it."

"I'm honored especially coming from you Admiral that you have so much trust in me for this kind of mission, but I'm not sure I'm qualified to lead something this important." said Alton unsure of his leadership skills

"No one is really qualified for something like this, it's not exactly taught at Naval academy, but someone has to do it, and our choice is you." said Hood

"How do you expect for me to get there?" asked Alton "Our current Shaw-Fujikawa drives can't make that voyage."

Osman had a grin on her face "That's where your wrong." The image on the table changed to a ship "Captain Alton allow me to present to you the first ship of her class, the UNSC Praeter."

Alton began reading the specs on the ship, and while it was nowhere as impressive as the UNSC's flagship Infinity, it was still a feat of engineering.

Osman continued her presentation "The Praeter design was created from the original phoenix class colony ship's, but the difference is the Praeter was created specifically for military purpose instead of redesigning it after, also the Praeter is 3.5 KL long instead of 2.5 KL long." said Osman as the image in the table began change to show other parts of the ship "The one most significant thing about the Praeter is it's knew slipspace drive procured from a Forerunner ship called the Audacity designed for the purpose of reaching that galaxy."

Alton was impressed with what he saw and could not find any problems "How long would it take to reach that galaxy?"

"Given the complexity with this new drive were dealing with, according to our scientists six months to get to the new galaxy." said Osman

Alton couldn't believe he was going to be making history as the first human to reach another galaxy "When I get to Path Kethona and discover the origin of the Flood, how do you want me to handle in destroying them?"

Hood brought up a file next to him "We have a weapon called the Nova bomb, it's a nuclear weapon created with nine fusion warheads encased in lithium triteride armor. When detonated, it compresses its fissionable material to neutron-star density, boosting the thermonuclear yield a hundredfold"

Alton whistle at the specs behind the bomb "I have to say Admiral, remind me not to get on your bad side." said Alton

"This bomb is just the cake, the icing is on your ship." said Hood

"The Praeter is equipped with an array of weapons, but it is also capable of building bases on planets just like the old Phoenix class ships." said Osman

"Do not take any chances when it comes to the flood, use everything in your arsenal to make sure you get the job done, leave nothing of the flood behind." said Hood, determine to wipe this plague from the universe.

Alton nodded his head "Yes sir, I won't fail you" said Alton determine to finish the mission through "When do I leave?"

"In three months the ship will depart for its maiden voyage, you and your crew will be in cryo-sleep while the Ship is on autopilot, the AI that will be assigned to your ship will remain in standby mode until you reached the galaxy."

"Sir, I understand my mission, but I have to ask" said Alton "What happens if I encounter alien life while I'm there."

Hood closed the hologram and stood up "Should you make first contact, assume hostility and present a first contact package." said Hood as he walks out of the room.

"Remember!" said Osman looking stern "You're on your own out there, there will not be UNSC high command to give you orders should you come across something unexpected and remember should the alien be hostile enact the Cole protocol."

Pegasus Galaxy

Present day

2555

UNSC

Praeter

Bridge

On the bridge of the Praeter the men and women in service were hard at work getting the ship in operational status. As that was happening the AI Yelena began using the sensors array on the Praeter to get a fix position of where they were and after several minutes she noticed a problem "Captain, we have a problem."

Captain Alton walks over the Holo table that Yelena appeared at "What have you got for me?" asked Alton

Yelena looked at the Captain with a stoic look, that things have not gone as planned.

UNSC

Praeter

Conference Room

In the conference room all senior level members were gathered to hear what Yelena had to report on the current situation. Apparently from looking at the sensor reading of the stars and correlating them with the information gathered in the Forerunner facility, she has explained they were not in Path Kethona and ended up in another galaxy.

"Where are we?" asked Captain Alton annoyed and angry at the sudden information Yelena gave him

"Unknown" said Yelena "The UNSC does not have information on any of the other known galaxies in the local group"

"But how can you be sure were not in Path Kethona? Or still in our own galaxy?" asked Captain Veronica Dare leader of the ONI contingent on board the Praeter. She was handpicked by Osman to lead a team of ONI into gathering any intelligence on the new galaxy.

"Current star patterns does not match the information in the Forerunner installation where the Audacity was discovered." replied Yelena "And the known star charts the UNSC has doesn't match these new stars."

"That information is 100,000 years old, and taking stellar drift into the equations the stars wouldn't line-up" said Dr. Robert Crane PhD in Astrophysics and Mechanical Engineering and head scientist on board the UNSC Praeter leading the whole scientific research department into unlocking any new technologies that they might find in Path Kethona.

"We did take stellar drift into consideration Doctor." said Yelena irritated by Crane's assumption that she would make such a miniscule mistake like a scientist fresh out of college. "Scientists along with myself made the necessary calculations before departing our galaxy."

"Then how did we end up in a different galaxy?" asked Dr. Allison Collins Chief Medical Officer on board the UNSC Praeter. Collins is the head medical practitioner on the Praeter responsible for the well being of the crew.

"It is possible we may have steered off course from our intended path and ended up here." replied Yelena

"Then how did that happened?" asked Major Faison, former Marine and ODST, volunteered for the Spartan IV program, he leads a Fire team and commands all Spartan IV's on the Praeter.

"That could take some time." said Yelena "I will have to filter through the sensor data to see what caused us to go off..." Yelena suddenly stopped at the end of her sentence abruptly.

"Yelena?" asked Alton trying to get her attention.

Yelena soon came out of her trance "Captain, I have detected an unknown energy signature originating from the habitable planet." said Yelena as the signature appeared on the holotable.

Dr. Crane walked up to the holotable and examined the signature. As he was doing that Captain Alton walked up to him "Doctor! What can you tell us? What is it?" asked Alton

After examination of the signature Crane turned to the Captain "The energy signature appears to resemble a wormhole."

"Wormhole?" asked Alton clarifying to Crane that he was not a scientist.

Veronica Dare joined the conversation "A wormhole or "bridge" is a hypothetical topological feature that would fundamentally be a shortcut connecting two separate points in space time." said Dare

Everyone was staring at her in silence including Yelena, Dare soon looked uncomfortable "What?" she asked "We do a lot more than intelligence work at ONI."

Crane shook off what Dare said and continued "Captain Dare is correct, now while we never have encountered a wormhole in our years of space travel does not mean they don't exist, it's just their random occurrences in space hard to predict when a wormhole will form, but I have never heard of a wormhole appearing on a planet." said Crane

"Theories Doctor?" asked Alton trying to change subjects and the fact that he let Lord Hood down.

"I have a number of theories of how, but we won't know for sure until we investigate." said Crane

But before Alton could think about investigating Dare intervene "I hope you're not considering of investigating" said Dare "Were not even in Path Kethona and do I need to remind you Captain of the Mission were suppose to complete." said Dare emphasizing on the word Mission.

Captain Alton looked at Dare with an irritated look as if he didn't know how important the Mission is. "Yelena, can we set a course to Path Kethona?" asked Alton

Yelena wasted no time in giving the Captain an answer "I'm afraid not Captain."

"Why?" asked Dare

"Travelling between galaxies requires a tremendous amounts of power." said Yelena

Doctor Crane stepped in on the conversation "Which is why the UNSC placed an extra reactor on the Praeter to make the Journey to Path Kethona and be able to make it back."

"Reactor energy has already depleted to a point where we only have enough energy to make it either back to our galaxy or keep going forward to Path Kethona." said Yelena "The latter being that if we do go and complete our mission and attempt to travel back to our galaxy we will have depleted all remaining energy and be drifting in the void for millions of years." said Yelena

Captain Alton leaned on the holotable thinking of how he could ever face Lord Hood for screwing up an important mission like this "What are our options?" asked Alton

"We could head back to our galaxy while we still have the energy and face the humiliation." said Dare

Crane then stepped in to give his own opinion "Or we could go check out that wormhole reading." said Crane

Everyone looked at crane with curious looks "All I'm saying is if we screwed up, I would not want to go back and face my superiors empty handed."

Alton began thinking and while it wasn't the mission he was assigned too, Crane had a point, better to go back home with something then nothing. Alton then activated his headset radio and contacted the bridge "Lieutenant Henderson tell the helmsman to set a course for the habitable planet in the system."

"Captain!" said Dare looking at him suspiciously

Alton faced his senior staff "Crane's right, I don't want to go home empty handed, dismissed."

As the senior staff left the conference room, Alton stood there alone for a while and shook off the sudden realization of being in a galaxy that was not the intended destination, he soon left the conference room for the bridge to hopefully make a discovery that would benefit his people, but what little did he know was that he was going to make a discovery that will change the history of his people.

So to clear something's up, I know Erde-Tyrene was the name pre-historic humanity called Earth in the Halo games, I didn't want there to be any confusion when the Atlantis expedition and Captain Alton meet and both claim their planet's are called Earth, so that's the only difference. Now some of you are wondering whether the Master Chief will be in my story, well if you had looked at the timeline for the UNSC there two years before the events of Halo 4, now I'm not going to put the event in my story, but it will be mentioned at some time when we get close to that year. Please leave any comments you have in the review section, thank you for reading my story.