You can't string together three sets of Christmas lights without losing one of them in 24 hours.

And then, like thousands do each year, you drive by Joe Lester's house in Tewksbury. There's a 48-by-26-foot American flag covering his roof, in 16,000 to 18,000 red, white and blue lights, its 50 stars aglow in white.

That's just the roof.

Up in Hudson, N.H., Marc Mousseau and his stepfather, Paul Roy, have erected a three-ring holiday circus on their front lawn. And that's just the theme part.

The two yards and the houses they front are covered in displays. Gingerbread men and Santas and trees and angels and reindeer are as plentiful as cars in a junkyard.

And up high on each display is Santa Claus in a helicopter.

The displays are lit Thanksgiving night and last for a month. But the work is never done.

It's a matter of planning, power and perseverance. It doesn't hurt if you're a bit obsessed.

They are Clark Griswolds, holiday artists of home and hearth, men on a mission to paint the night in amperes. They ask nothing in return but smiles, traffic courtesy and perhaps a little something in the donation box, which goes to charity.

It is not easy. Over the years, these dedicated denizens of December decor have worked in deep freezes to hunt down that lone light that is cutting off the rest of them. They scale roofs, and crank up the juice. Last year, Mousseau blew two utility-pole transformers before the first weekend was out.

They also know one another as members of an elite group of area holiday lighters. They keep abreast of one another.

Lester, 38, is an impressionist, working from memory and on a whim. Mousseau, a 36-year-old carpenter for the Lowell National Historical Park, and Roy, 67, are deliberate Michelangelos. They have a Web site, www.hudsonchristmas.com. Roy keeps a spreadsheet that lists every decoration, its number of lights, grouped by yard location. He pulls a thick file of preliminary sketches, as Versace designers keep.

They don't shop so much as hunt. Lester scours "every store from here to the Connecticut border" for "the stuff nobody else has." Mousseau and Roy attend an annual summer convention of holiday home decorators in Tennessee.

Roy, who is retired and is "a sucker for the animated stuff," raids decoration stores beginning the day after Christmas.

"I plan everything and he gets up on the roof."

He moved to Hudson in 2001, after retiring from the U.S. Air Force and human-services work.

"You know, I never decorated anything in California," he says.

Their friends?

"Well," Mousseau says, "they all come by, but some of them think we're sort of ... obsessed. But they all think it looks great."

Lester upgraded his house electrical service to 400 amps this year, powering some 175,000 bulbs twinkling in the winter night. He estimates he uses 350 extension cords.

"Yeah, 400 amps, that's just crazy," he says proudly.

A decade ago, he started with a typical 100 amps. Three years ago, he added a generator. Two years ago, he upgraded the house service to 200 amps. Last year, he added another generator.

"But adding 400 amps. That's a lot," Lester says. "You could run a welding company with that. It's what's in an industrial building."

Lester has 28 outdoor outlets on his house.

His typical electric bill in December is $1,500.

Mousseau will run his display off 200 amps in his main house and another 200 in the "Men's Club," an adjacent garage and recreation room.

Both collect for charities with donation boxes out front.

In Hudson, this year's collection will go to benefit Matty Dubuc, a 7-year-old with a rare form of liver cancer.

In Tewksbury, Lester wanted to collect for Jack Lynch, a 4-year-old boy with cancer. The boy died this week.

"I'm just heartbroken," Lester says.

None of them is an electrician, though Mousseau's trade allows him a certain familiarity with voltage. He ascends a 24-foot extension ladder to decorate the roof. Lester used a bucket truck this year for the first time. He revamped 70 percent of his display, replacing faulty lights and cords.

"Everybody assumes I'm an electrician," says Lester, who works as a manufacturing manager. "I go from past experience and read a lot about it online. The wiring part, nobody does it -- nobody touches it -- but me."

He uses an amp meter to check everything.

Lester's son, Justin, 5, and daughter, Jennie, 1, "love it all." His wife, Stacey, is "very supportive. You know, it's a bit of a burden on her. I mean, I'm mostly out here... ."

He starts Labor Day, pulling everything out of the shed on the back of his house, taking inventory.

Thick wires run along the sides of both houses and onto the lawn, like orange spaghetti. They meet small portable outlets there.

The house in Hudson uses computers to make a tree of lights blink to the beat.

Mousseau and Roy begin the last weekend in October. Their first "big" year, 2002, they set up 40,000 lights. The following year, 80,000. Then, 100,000. Last year, 140,000. They have an inventory of 250,000 lights.

"So we've actually scaled back with 110,000 this year," Roy says. "We decided to concentrate on a theme of a Christmas circus, a three-ring circus on the front lawn."

Mousseau took a welding class earlier this year to learn to make the 6-foot-tall hot-air balloon sculpture near the driveway. Four feet wide, it is covered in 2,300 multicolored lights.

"On and off, it took maybe three days," he shrugs.

Mousseau and Roy and Lester have become friends. There's a hint of one-upmanship, though.

"We're the two largest displays around here, though mine is bigger than his," Lester says. "He does a lot of yard stuff, but I have more lights, more power."

Lester recalls a visit three years ago, in which Mousseau and Roy braved a huge clot of traffic in front of his house to talk. "He had a lot of questions," Lester says. "We share ideas now."

Mousseau doesn't recall asking for advice, beyond maybe how to handle donations.

"We were both in the paper within a day or two, so we were aware of one another. There's nobody else at this magnitude. Joe is the closest I know of. The next closest guy to here is up in Raymond, N.H.

"Joe will call and say, I'm thinking about getting this or that. He called about getting a Ferris wheel the day after ours arrived."

In Hudson, at 75 Pelham Road, it all comes down the day after Christmas.

In Tewksbury, at 220 Cabot Road, it ends after New Year's Day.

If it ever really ends.

A few years ago, Marc Mousseau and his stepfather, Paul Roy, ran their entire display off 200 amps.

"We had extension cords out the window, running from the garage," says Mousseau. "And you could only do things at certain times. Two years ago, you couldn't run anything electrical from 4:30 to 10 p.m., when the display was on."

Last year in Hudson, one of the thick orange cords sizzled and burned, but the damage went no further.

"I bought that at a flea market," says Mousseau. "It said it was rated for more than it really was."

Be prepared to spend, and spend some more

"Start slow and build," says Mousseau.

"It would help to have a nice bank account," adds Roy.

If you go large, be prepared for everyone to show up

"We get buses of elderly people," says Mousseau. "School buses. Limousines. And there's this office-party bus from Burlington with drunken people. They got out and began running around the lawn where all the cords are. I had to run out and say, 'Whoa, wait a minute!' "

-- DAVID PERRY

David Perry's e-mail address is dperry@lowellsun.com.