I love 'em, they all seem to be stamped out with a cookie cutter, different ingredients but the same recipe.
1) The disaster is always due to an incredible coincidence or exceedingly improbable event (tsunami capsizes cruise ship, rogue comet threatens earth, coronary victim light plane pilot crashes into jet airliner, etc.
2) The authorities always know what they're doing and do a great job handling the emergency, except for one obstructive and skeptical bureaucrat who usually dies in the third reel.
3) The bad guy, usually an evil corporate pirate, gets his comeuppance in the end, usually an ironic horrible death of his own devising. This is the biggest fiction of all, in real life, evil corporate pirates always get away with it.
4) There is always an obnoxious little kid, a crusty old codger (with a heart of gold), an angst-driven hero, a matching pair of teen hearthrobs, a sympathetic black guy (he usually plays the role of Star Trek redshirt), a faded but still seductive courtesan (also with a heart of gold), a spoiled heiress, and a coward (usually overweight). The latter usually redeems himself...just before he buys the farm. A nun or priest is optional, prayer always plays a role in these events.
5) When it's all over, we know the solution to the problem is now known and IT CAN NEVER HAPPEN AGAIN.
Speaking of disaster movies...
