A synopsis for an idea I had for an AvP would be...
an opening scene:
The movie opens on an alien looking forest (nothing too strange, just enough to show its not Earth) the screen the turns to an advanced targeting system scanning the area, highlighting and locking onto a human silhouette. Then it cuts to a man in the middle of the this forest, visibly distressed and armed with a shotgun. Suddenly a loud strange roar is heard and the sound of an approaching beast. As it clears the trees the powerful looking alien (not xenomorph alien, just generic) is seen for just a second as the man jumps out of the way just as a shot is fired, killing the thing. It is revealed that the scope view from earlier was from another man, the two were hunting this thing. The screen pulls back and reveals a large facility not far from he two men. As they approach the kill, an alarm sounds on their radios. They begin to quickly make their way back to the facility when one of them is blasted by a predator (pred of screen). The remaining hunter, no panicked (obviously) sprints back, only to find the place a mess. Buildings are burning and an alien (xeno) is heard. The screen cuts to black. Title card blah blah...etc.
The basic premise is a few years after that event, lets say 20, the facility is rebuilt. It is a few years before the events of 'Alien'. Its a mining facility owned by WY (go figure). There were no survivors of found after what the company tells people was a worker revolt. A gas line was ignited and caused the whole facility to go up and turned the place into an inferno for weeks. (no evidence of the xenos are found). The facility (which will e revealed to have been not that valuable and on the edge of failure, but the company poured 5 times as much money into the rebuild) now has a small security team/ police force, and a large scientific/ research department to study anything new found by the diggers.
The main protagonist would be a man (call him: John) who just got a position as a supervisor at the facility. I figure the firct scene after the title card sequence will be him, in a WY office during the end of his interview for the job, and the employer implies he barely got it, and only did because a friend of his in the company championed him. (during the film it will be revealed in bits and pieces that he was in the Army, and has a wife and kid. It will them be reveled that he was injured on duty, discharged, became addicted to painkillers, lost his family, cleaned up and got this job.) Some other characters will include the chief of security, some diggers, and one or two scientist. Basically there would be decent character development, and backstorys. The time will be spent to establish them.
Ok, so the action. First trouble starts when there is a lot of comotion outside the facility walls. Remember those aliens being hunted int he beginning? They are migrating, and these (very deadly) creatures are not very violent (lots of infighting). The predator is hear during this time hunting them (though he doesnt cause trouble for a while yet). The facility is also getting ready to go on lockdown for a while. This migration happens a few days before a storm season. The facility will be on lockdown for about a week, and virtually isolated during this period due to the intense storm. Predictably the aliens are found while mining (I figure it would be in some sort of Space Jockey vessel) just before the lockdown. Several miners that find it are hugged. After a while people notice they are missing (thisgs are in chaos with the upcoming lockdown) and go looking, it has been enough time for the aliens to burst and mature, the miners sent to find them also go missing (again, go figure). The building is evacuated, John (the supervisor) is sent to the security station to give his statment and the security team is sent into the mine. yada yada, scene reminiscent of 'Aliens' and they are wiped out. The building is quarantined. The storm hits, communications go out.
The aliens get loose, the predator starts hunting them. The pred gets taken out and self destructs (under ground or in one of the bulidings. Lots of damage, but not destroying the entire place), but sends a signal. Several preds come later (like 4 or 5, but they all HUNT, not fight like AvP1). Chaos ensues. The ticking clock in the movie would be something like the first preds detonation triggered a massive leak in some gas and also set the stage for a massive volcanic eruption under the facility. The people eventually realize this, and as soon as they can (and after a single alien gets inside their bunker and compromises it) begin to make their way to a small survey shuttle on the other side of the facility to launch into space, get into orbit and send a distress signal. The movie will take place over about a week.
The survivors are picked up. One of them turns out to be an android (not a crazy one like ash though) and the facility is destroyed, and the entire area. The company decides to label this another revolt, led by John, who will be sent to prison but the company officials say that his freezer will malfunction in transit (ie: they will kill him). The info will be taken from the android, and it will be scraped. The information will then be used to search and match signals from the vessel at the mining facility to any other SJ signals, and company protocol is then to investigate all findings (ie: what Ash did in 'Alien').
I got very lazy in my description, but I actually have several outlines for sequences and fights in my head, detailed ones too. Oh, and the pred lives. A final pred, very messed up (little equipment left, arm partially melted off, etc.) begins to make an escape, finds the queen. Tries to take it out stealthily, does some good damage, tries to fight it but is far to injured and ill equpied. It runs, but it just sets a trap that the queen gets caught in, and dies (a trap, and sequence, reminiscent of Predator1 with dutch and the pred).
I came up with most of this while watching AvP:R.
