The 300-word (max) pitch I'd prepared went through a number of edits (mostly tonight, to tell the truth). I received a lot of helpful suggestions from friends, most notably from fellow author Kim Stokely, who always sees things I don't. Thanks, Kim!
So...here's the version that went forward:
THE MENGELE EFFECT
Science Fiction/Fantasy/Horror Category
On the last night of mankind's reign, the Reaper rides the wind, and falls from the clouds.
A single raindrop is the catalyst which opens a Pandora's box of genetic horrors, long-forgotten amidst the rusted steel of a Kansas City salvage yard. The mutations spread swiftly, and a new species catches the scent of prey. Dawn reveals a dead city, eerily quiet and still. The mutant beasts hide from the light, multiply, and await the shadows of day's end.
Biowarfare specialist Carolyn Ridenour fights a daily battle to keep America safe from the world's tiniest, most fearsome weapons. Ordered to investigate the unfolding crisis, she barely escapes the creatures' nocturnal onslaught, saved at the last instant by Colonel Garrett Hoffmann, a man who'd lost hundreds of his troops to a furious wave of things bombs and bullets couldn't slow. Together they work to halt the plague, but time is short. Frantic for answers, President Andrew Smith is pushed to consider unthinkable action by members of his own government, trusted advisors who have long prayed—and prepared—for this day.
Carolyn and Garrett race to stop the creatures—the spawn of perverse genetic research performed in Auschwitz’s filthy labs, refined by Cold War enemies and perfected by nature—before a desperate President unleashes the fury of America's nuclear arsenal on his own soil...and his own citizens.
Wish me luck!