A/N - Well, this is my first attempt at writing a Halo fic. I just happen to be playing Mass Effect at the time and thought this would be a great game to X-over with the Halo Series. If you can't tell, It starts off just after Halo 3.

Review if you feel like it. Thx!

Chapter One

"Chief… can you hear me?"

Master Chief groaned as his bones creaked and squeaked as he emerged from his stasis pod. He blinked a few times to let his eyes adjust to the surroundings after being closed for so long. He floated over to where Cortana's image was projected onto a nearby terminal.

"How long has it been?" Chief asked.

"Approximately five years chief. But that's not our main concern right now," Cortana answered, looking to get straight to business, "We're rapidly approaching a planet that I cannot identify. We have to evac. The Dawn can't handle an atmosphere entrance in its current condition."

"How much time?" Chief asked, already reaching for his battle rifle, which was attached to the wall nearby.

A string of ones and zeroes passed through Cortana's body. "Since I can't slow us down, and at our current speed and trajectory, I'd say five minutes maximum."

"Any ideas?" Chief said, looking around him for more of his weapons.

"Our only option would be to use an escape pod. Even then, it's still risky. I'll explain the details as we make our way to it. Now yank me," Cortana said, her image disappearing. John put his hand on the console and felt the familiar tingle as Cortana entered his suit.

"It's good to be back in here," Cortana noted. "Now, let's get a move on. You're going to have to…" The Chief scoffed as he left the room as Cortana detailed their escape

----------

Master Chief had filled the escape pod with as much ammo, weapons, and rations he could find, not knowing what was waiting for him.

"Thirty seconds until atmosphere entrance," Cortana's voice chimed.

"Do you know anything about where we're going?" Chief asked, as he did a mental count of his ammo.

"Well, I've determined that the atmosphere is breathable, but almost ninety percent of it is covered in lava. Our percentage of landing on dry land is—"

"I'd prefer not to know," Chief said, cutting her off. "How far are we from Earth?"

"Frankly, I don't know. As a matter of fact, I have no record of this system we're in at all. We could be millions of light years away," Cortana answered.

Master Chief frowned, but his thoughts were interrupted as the pod shook violently.

"Hold on Chief, we're entering the planet's atmosphere, it's going to be—wait! I've detected contacts! Stand by, we could be landing somewhere where we're not welcomed," Cortana's voice came, clearly alarmed.

"How comforting," the chief said as he grabbed onto the sides for support. Again, the pod shook violently and the chief sneaked a peak through window. He could see flames as friction from the atmosphere pressed onto them. After about a minute, the flames died down, and he could see what appeared to be land rapidly approaching.

"Brace yourself chief!" Cortana's voice shouted just as the pod made contact with the ground. Master Chief's head slammed on the bulkhead behind him, almost causing him to lose consciousness, but somehow fought off the pending darkness that tried to overtake him.

"Chief, are you alright?" Cortana's voice filtered through as he fought off a massive headache.

"I'll live," he said, already sure that he had a slight concussion.

"You'd better, because I detect a contact closing in on our position. Be alert."

Chief confirmed this as dot emerged onto his radar. What was strange was that it was identified as friendly, but Chief wasn't going to take any chances. He readied the nearest weapon, which was an SMG. With no other option, Chief reached up and opened the hatch, SMG at the ready. As soon as it opened, he was met with a weapon in his face. The Chief alertly raised his own weapon.

"Well, you're certainly not geth," came a voice. A second later, a woman's face popped into Master Chief's view. "So who are you?" the woman asked, gun still pointed in Chief's face.

"You first," the Chief said, not budging.

"Straight to the point are we? Well, I'm Commander Alice Shepard of the Alliance Navy."

"Never heard of it," Chief replied, weapon still at the ready.

The woman, Shepard, frowned. "You've never heard of the Alliance Navy? Are you lost? Who are you?"

Chief was about to respond, but Cortana beat him to it. "We're from the United Nations Space Command."

"Never heard of it," Shepard replied, "And why do you speak in two different voices?"

"She's my AI, Cortana. She helps me out in the battlefield," Chief responded.

Shepard and Master Chief stared each other down for what seemed like forever. "Well, you're definitely not a geth, and you're not hostile," Shepard lowered her weapon, raised her arm and signaled, causing two more hidden people to emerge, which Chief didn't even spot. "It's okay, the coast is clear," she shouted.

Hearing this, Master Chief lowered his weapon as well, more than happy to avoid a firefight. "What is this planet?" he asked as he lifted himself out of the pod. He stood straight up, about two feet taller than Shepard, who was standing next to him.

"You're on Therum," a new voice responded. Chief looked over to see another young woman inspecting her pistol. She locked eyes with him, and for a second, the Chief was lost. But it didn't last long as a rough voice cut through.

"Nice landing," Master Chief looked over and was surprised to see what looked like a giant lizard, except it (or he?) was as tall and big as the Chief himself, and carried a shotgun. Wondering what he (or it) was talking about, he looked down to see that his pod had crashed down onto what looked to be the remains of a large machine.

"You certainly did us a favour," said the woman inspecting her pistol. "I'm Ashley Williams, and this giant heap next to me is Wrex."

"Fifty credits say 'this giant heap' could whoop your ass," Wrex replied smoothly.

"Can it you two. We still have to find that Asari named Liara. We don't have all day," Shepard said, trying to get back on track.

"Asari? What's that?" Cortana asked, her voice booming through Chief's helmet speakers.

Wrex and Williams stopped bickering and stared at the Chief like he was crazy. "You've never heard of the Asari?" Williams asked, clearly shocked, "Damn! You're definitely not from around here!"

Master Chief just shrugged.

"Look, we'll discuss that later. But for now, we need to get going," Shepard said, readying her weapon, which looked like a supped up UNSC standard assault rifle. "Would you care to join us?" she said, holding out her open hand towards Master Chief.

Master Chief gave it only a seconds' thought before reaching out his own arm and shaking the Commander's hand. "Might as well. You seem to know what you are doing."

Shepard laughed. "Nah, were kinda just wingin' it as we go. Welcome aboard Master Chief, if you're okay with me calling you that."

"That'll do, ma'am."

"Okay then. My partners and I will search the dead for any upgrades while you get yourself loaded up," And with that, Shepard raised her arm and signaled again, then jogged off in another direction.

"You sure about this Chief?" Can we trust them?" Cortana asked as he began to load up as much weapons, ammo, and grenades as he could walk with.

"We don't have much of a choice. Maybe they'll be able to help us figure out just where the hell we are. Plus, I'm not fond of the idea of sitting out here in the open with no means of escape," he replied smoothly. "Besides, I'm kind of just wingin' it as well," he finished, quoting Shepard.

"You don't have a plan?" Cortana asked, mildly surprised.

"Please, I've been improving ever since we landed on Alpha Halo."

"I knew it! You bastard!" Cortana said, sounding almost offended.

Master Chief could practically picture her smirk as he approached the Commander, trying to fight off his own smirk, failing miserably.

For the umpteenth time in his life, the Master Chief was walking into a situation not knowing what lied ahead of him.

Like it bothered him any.