Time Immemorial

Any good creative writing teacher will tell you that your first sentence should grab the reader and pull them in. Then your story must hold on to them for dear life. So how do I begin?
A long time ago, in a galaxy far, far, away...... no wait that's been done before, how about this.
Once upon a time...... No sorry, that's been done to death. Here we go again.
In the Beginning......... Stop Stop Stop, I know I've read that somewhere before. Oh yeah now I remember where.
Let's try something else......
They came from the planet OM. (Pronounced like ohm: The unit of electrical resistance) This may or may not be the name of their native planet, but it's the closest phonic sound we have to what they called it. They talked about going OM when the mission was over, and how much they missed OM, and how there's no place like OM for the Olidays. (Now you know where the Cockneys got their accent from.)
Now the planet OM has quite an unusual rotation and orbit. Its orbit is so elliptical that in a given "year" on OM they were closer to their sun than Venus is to ours and then farther away than Mars at the other extreme. The term "year" and "day" were also misleading because OM's axis of rotation was nearly parallel with the plane of its orbit. In layman's terms, OM lay on its side and spun around with the sun making ever widening circles in the sky until it dropped below the horizon for half of the time.
It was because of this that the inhabitants of OM lived in a very narrow band around the planet, as the temperature on most of the surface was either too hot or too cold for life to exist. Life was tough but the people were tougher. The planet originally had a protective layer in the atmosphere that shielded the inhabitants from excess ultraviolet light and retained the heat that their sun provided. But over time, and due to excessive pollution their civilization had not found a solution for, this layer was lost and life on OM was in peril. (Sound familiar?) Fortunately the scientists had found a solution for their dilemma by seeding the atmosphere with a compound made from the elements Hydrogen, Oxygen, and Gold.
Now Hydrogen and Oxygen were plentiful and could be found wherever there was water. But on the other hand there was only a limited supply of the element Gold, and after many years of going up in smoke this resource was running out. This compelled the leadership of OM to embark on an ambitious quest. Fueled by their advanced scientific knowledge and powered by their will to survive, they devised a plan to journey to other planets, genetically engineer the indigenous species found there to enable them to communicate well enough to relay working orders, and harvest them for the gold needed to survive.
Their spaceship was an enormous vehicle, equipped with the finest biological facilities and weaponry they could muster. It was called the ARK, and its crew were known as the Ark-ons. They were later to become known by the more familiar name "The Archons". They traveled to new worlds and either enslaved the indigenous beings they found there or genetically altered the existing fauna to satisfy their insatiable thirst for Gold.
Many of these planets were easy to conquer at first, but by giving the inhabitants the power of speech or other communication methods, it wasn't long before insurrection arose. The Archons were compelled to use more and more force to quell these uprisings. The ancient history of these planets were filled with lore of godlike beings, flying through the skies on magic chariots, emitting lightning and fire from their weapons and even from their very being. These were not fantastic fables of mythical creatures but the actual observations of the inhabitants that were enslaved.
So life evolved on these planets and eventually the Archons were either eliminated or left on their own for greener pastures. However the DNA of their experiments was woven indelibly into the worlds they left behind.