Remember that creepy feeling when you feel something land on the back of your neck?

About a decade ago, millions of cicadas swarmed the D.C. metro area -- terrifying some people, pestering others and soiling at least a few pairs of shoes as cicadas crunched underfoot, turning into a buggy-mush.

"Looking out on the street, it basically looked like there was a river flowing down it," recalls John Lill, assistant professor of biology at George Washington University. "There were thousands of cicada nymphs flowing down the road."

Well, they're back.

Good eatin'
When cicadas are in abundance, it's time to feast.
Edward Barrows, a biology professor at Georgetown, said he had a neighbor who popped molted cicadas into his mouth uncooked.
"He was picking off the whitish ones and he was just chewing on them and swallowing them," Barrows recalled.
Others saute them in butter.
A colleague of Barrows baked them in chocolate and pushed the six-legged chocolates on her co-workers.
"She had the greatest time trying to get people to eat them," Barrows said.

Brood II -- the ominous sounding name for one group of cicadas that returns every 17 years -- will climb out of the ground in states running between North Carolina and New York by the end of the month.

In the dead of night when the temperature is just right, they will emerge from the ground, climb into the trees and the males will emanate a pulsating sound that keeps suburbanites lying awake in bed as these insects search for a mate.

But, said Gary Hevel, a research collaborator at the Smithsonian: "The adults don't last too long."

Within the span of a few weeks, the cicadas will come and go, transforming from young nymphs into full-fledged adults. Often attaching themselves to a plant stem, the brown nymph -- with red eyes and black markings above them -- transforms. It sheds its exoskeleton and a ghostlike white creature is revealed. And still its eyes remain that haunting red.

The white, soft-bodied creature that the cicada has become, having abandoned its crunchy skin, is particularly delectable. Squirrels have been known to gorge themselves on the protein-filled creatures. Presented with this unexpected smorgasbord, pets -- dogs more than cats -- will also overeat. Fairfax County even issued a warning against letting pets eat too many, which can cause constipation if consumed in large numbers.

Entomologists say people really have nothing to fear when it comes to cicadas: They don't bite, they're not poisonous, they don't sting and they don't stick around very long, anyway.

Still, they can be a bit unnerving when they arrive in great numbers and essentially take over a neighborhood. They have even been known to cause car crashes by distracting creeped-out motorists. "It can be a frightening experience when one lands on your shoulder or on your head or toward your eye," Hevel said. "They've got to land someplace -- and sometimes it's on a human."

Cicadas are pretty big as far as insects go. Fully grown, their bodies are longer than the diameter of a quarter and their wings are two to three times as wide.

The good news: The District and surrounding suburbs are expected to get only a spotty showing of the Brood II infestation rather than the full-fledged invasion during 2004's Brood X. Still, parts of Maryland and Virginia can expect to be bathing in cicadas within weeks.

At the end of it all, after the eggs are laid in pencil-sized twigs, millions of semi-translucent empty insect husks will litter the ground, memorializing the cicada circus that was -- and will be again in 17 years.