The house stands shrouded in an unnatural fog. A desiccated corpse hangs from the basketball hoop in the driveway. Two carrion birds perch protectively over the skeletal remains. Large and venemous-looking spiders have covered the bushes with a dense gauze of webbing. An eerie green light plays over the whole scene while sepulchral music and low moans and groans emanate from unseen sources. Everywhere one turns, the undead are rising from their graves and lurching forward into the night. Here there be monsters.

The setting is not from the latest Hollywood horror flick or even from a particularly disturbing dream brought on by too much spiced cider. It is just the annual Halloween display set up by the Addams, er, Mohrmann family in the family's front yard in the Rose Hill area of Franconia.

For the last seven years, Cindy, George and Barrett Mohrmann have gone to extraordinary lengths to ensure that theirs is the scariest yard in the neighborhood on Halloween.

Dad, who spends late October evenings haunting the yard as Frankenstein's monster and weekdays working for Lockheed Martin, credits the idea to a then-6-year-old Barrett.

"He came up with a scheme and said, 'If we make this house scary enough, nobody will come and trick or treat, and I'll get all the candy myself.' That was his logic."

So far it hasn't worked. Neighborhood children and adults alike make the Mohrmann home a much-looked-forward-to tricking and treating destination. Even so, Barrett, now 13, says of the smaller children, "It's always funny to see how many cry."

The number of decorative details are extensive, but the yard's centerpiece is the "Dismal Hollow Cemetery." Here, under the spreading branches of a vampire bat-infested cherry tree, is a low fence that encompasses a dozen or so simulated gravestones emblazoned with verses such as, "Beneath this stone old Abraham lies. Nobody laughs and nobody cries. Where he is gone and how he fares, nobody knows and nobody cares."

But it is the plastic-severed body parts and evil-looking rubber rats scattered among the gravestones that are the real scream-inducers here.

The cemetery is also home to the Mohrmann's newest acquisition, a life-size model of a bloodied corpse tearing itself from the ground. He is known affectionately as "the Dead Guy."

The Mohrmanns aren't used to doing anything halfway. They mention an elaborate Christmas display for the yard and describe several "high concept" birthday celebrations.

Their passion for Halloween decorating though is what gets them noticed. A recent conversation at a local restaurant got the family some strange looks from the patrons at an adjoining table when Barrett mentioned that it would soon be time to "take the Dead Guy down from the attic."

Cindy, a stay-at-home mom, says the annual process of decorating the yard is "a family project" with even Barrett's grandmother and uncle pitching in to help make sure the crowd of jack-o'-lanterns on the front porch looks just right.

It is Cindy who is responsible for most of the handmade decorations. With degrees in biology and interior design and work experience in Inova Fairfax Hospital's morgue, she may be uniquely qualified to determine the most aesthetically pleasing way to place a severed head in a flower bed.

It was while she was in college at George Mason University that Cindy answered an ad looking for someone "who could work with maggots, blood and body parts. I thought, well I could handle that." That part-time job in the medical examiner's toxicology lab led her to additional work in forensic science for several years. She is eager to point out, however, that "I've had some normal jobs, too," including doing DNA research and designing displays for a home furniture store. Still, "Barrett loves it when I tell morgue stories."

While George describes his role as "hammering and sawing" and Cindy is the production designer, Barrett is the annual project's visionary.

"He tells us what the yard needs. He is the director," Cindy says. "If he didn't like Halloween, we wouldn't be doing this." She admits that Barrett's status as an only child and health problems she had related to her pregnancy and his birth have led her and George to indulge Barrett's whims. "The fact that he exists is a miracle. So he is spoiled rotten. This is a labor of love."

Barrett says of the holiday, "If I could, I'd probably make Halloween every day of the year." And while he enjoys Christmas, All Hallow's Eve is never far from his mind. For Christmas last year, the gift he enjoyed most was a new corpse for the display.

"I love scary movies; I love scary books," he says, citing R.L. Stine's "Goosebumps" series as having had an influence.

While showing off the new wooden vampire cutout his mother is finishing in the garage, Barrett points out that it will be the companion to the lady vamp already on the lawn. He calls her Lily. " 'The Munsters' have always been a big favorite of mine."

When asked if he has any particular career aspirations at this point in his young life, Barrett mentions the possibility of becoming a veterinarian. He likes animals and is the proud new master of "Killer," an 11-week-old West Highland terrier. Barrett has had a long line of pets including dogs, cats, hamsters and fish. Oh, and don't forget the tarantula and the scorpion.

On Halloween night this year, trick-or-treaters can expect to get the whole scary experience at the Mohrmann home. Not only will the music be playing, the fog machine be pumping and the strobe lights be flashing but the family will be all be dressed in their spooky best.

For now, the family is putting the finishing touches on the display, making sure all the details are right.

"We put all the body parts in the cemetery this year," Cindy says. "I don't think there are any loose arms lying around."

The Mohrmann home is at 4405 Eaton Place in the Rose Hill section of Franconia.

Cindy Mohrmann arranges a Halloween decoration in front of her home in Franconia.The Franconia home is transformed into a ghoulish scene each Halloween with the help of Barrett Mohrmann, 13, right. Cindy Mohrmann finishes details on a new decoration, below right, for the front yard. Barrett came up with the idea for the display at age 6 as a way to scare away trick-or-treaters. The ploy never worked.Cindy and George Mohrmann finish up the display, which features a graveyard, rubber rats and fake body parts.