A/N:I finished study early, so I thought I'd post this.

Okay, this chapter references 1x16 Unleashed, which is where the 'creatures' for this fic sort of originated from. This chapter is short, but it's meant to be an explanatory chapter.

**the way I've decided to write these is so that each chapter is a month of 2011, showing their survival, what happens...etc.

Chapter One

10 Months Earlier – November 2011

Walter's lab was the safest place in Boston. Broyles had had a reinforced 12 inch steel door to replace the labs doors, and bars on all the windows after one of Walter's wacky experiments 'came to life' and injured Astrid and several students. Broyles wanted to make sure that none of the experiments got loose. So when the world ended, nothing could get in the lab.

At first it was just Peter, Olivia and Charlie. They had stayed in the FBI building when the creatures returned to Boston.

Almost everyone who ventured outside was attacked and killed. At least, being in an FBI building there were plenty of weapons, either in locked rooms or on the bodies of those who had fallen. Charlie was the first of the trio to venture outside. Olivia and peter followed next, but the 18 surviving FBI agents holed up. Charlie had told them to lock everything and seal themselves inside. They bolted the doors, blocking any access with furniture and traps. But they all knew, once the food ran out, they would have to venture outside.

The trio gathered food and water, and things they thought would be useful, lighters, clothing, weapons.

They explored the ruins that had claimed Boston, finding the bodies of many, and pieces of others. There were groups of survivors, mainly adults. The remains of the local school harboured dozens of bodies. Children. Upon seeing this, Olivia's first thoughts were of Ella, and Rachel. Had they survived? Will they survive until Olivia finds them?

Charlie eventually found John Scott and Broyles, when the trio separated in the hopes of finding anyone else.

They had been with Walter and Astrid at the lab, having locked themselves inside.

Ella was next. She had broken her arm and was crying profusely when Peter found her. She was slumped over her mother's body. Ella said that the creatures got Rachel while she protected Ella.

Now protected in the confines of the lab, Ella, Astrid, Walter, John, Charlie, Broyles, Peter and Olivia settled in for the long haul. No one knew how long they'd be there, how long they'd survive.

John and Broyles got a little trigger happy, managing to capture a creature for Walter to examine. Unfortunately, Walter didn't learn more than he had nearly 2 years ago.

2 Years Ago – 2010

With Charlie and John's help, Olivia and Peter managed to capture the original creature. A hybrid of sorts. It was similar to the creature that had attacked Charlie, laying its offspring and nearly killing him. Walter believed this creature was created from the biological 'plans', as such, of that creature. Walter did several tests on the captured creature, learning that it was either a mutation or an evolution of the Desmodus Rotundus (common vampire bat) combined with a Hydrophis Belcheri (Belcher's Sea Snake).

The sea snake's genetics was added to the bat, the bat being the 'base' creature. The snake allowed the creature to swim extremely well, able to survive long period's underwater, it also had poisonous venom, which combined with the bat's fangs, gave it an extra hunting ability. The creature got everything a Common Vampire Bat would have, Echolocation, the ability to fly, and its need for blood.

After interrogating its creator, Andy Norman, he revealed that the creature was created, raised and experimented in a near light-free lab. Because of bat's sensitivity to light, they thought it prudent to only use light that was necessary, when night-goggles didn't work.

The creature's had one weakness, light. Sunlight, UV light, torches, lamps, even fire. But with an 'allergy' (as Walter so colourfully put it) to light, that meant that once the sun went down, as soon as it became dark, no one was safe.

Broyles was having the creature moved to a secure location when it broke free, escaping.

The creature had made it as far Central Manchester before they managed to kill it. But not before it had bred, and those offspring reaching maturity in a matter of days, split off, roaming free.

The offspring then bred themselves, spreading further and further out into the world.

The first international incident was March 2010, 2 months after the original creature escaped. An office building in Ipswich, England was attacked, 89 employees were killed. From there, the creatures spread to Europe, Asia, South America and eventually Australia and Africa.

America had just been the starting point.

The world was reduced from billions to thousands by July 2011.

A/N: Okay, so hope that was okay, short I know. I figure, I'll write what I can between exams, and free time, so I may be able to post another chapter by Wednesday