Hello, hello?

The cellular telephone signal is weak. Sometimes it disappears altogether. He steps into the creek bed itself, his faithful puppy, Buddha, splashing at his side.

"The service is stronger in the middle of the water," he reports.

The call goes through, but communication is frustrated for another reason: His girlfriend is not at the other end to receive it. He leaves a message.

It wasn't a matter of life or death. Rob Christopher-Strayhorn wasn't trying to report a crime or an injury or that he forgot to turn off the stove. He just wanted to make plans to take Buddha to dog-handling class later in the day.

The Rock Creek Park dead zone--a couple of square miles of spotty cellular service--is the last large obstacle to Christopher-Strayhorn's instantly-in-touch existence. The 30-year-old architect's black, palm-size device is always with him, always on. His home phone is quaint, second-string technology. His cellular number is the one he gives out to friends and clients.

"I like to be reached instantly if somebody needs to reach me," he says. "I think that's where things are headed. People who don't think in these terms are behind the curve."

So many people do think in these terms that the Rock Creek dead zone is increasingly cast as a freakish anomaly, the Bermuda Triangle of wireless Washington. In the idiom of the ancient world explorers, a cellular map of Rock Creek Park would be marked: "Here Be Monsters."

Bell Atlantic Mobile hopes to civilize this wild country, in the form of a 100-foot antenna pole at the park's tennis center and a 130-foot antenna pole at the maintenance yard. Sprint PCS, the provider used by Christopher-Strayhorn, says it would like to put its own antenna on one of the Bell-Atlantic poles, and other companies could do the same.

Advocates say cell phone service in the park will improve public safety and convenience. Opponents argue the poles will mar the view, endanger migratory birds and possibly blaze a trail for yet more poles in Rock Creek and other parks.

While Congress mulls the matter, the dead zone is the perfect place to get in touch with the vanishing concept of being out of touch.

Here are Wendy Bernstein, 36, and Steven Schauder, 34, walking with their son Max Schauder, 7. Car traffic is closed on this section of Beach Drive for the weekend. The only sound is crickets, whose chirp is not unlike that of a portable, and the wind soughing in the trees.

Bernstein and Schauder recently bought a cell phone, but they did not bring it. They are blissfully incommunicado.

"Doesn't a city deserve one pristine spot?" Bernstein says. "I'd like to have a place in the world where there were no cell phones."

The reason they broke down and acquired a cell phone is that Bernstein is pregnant again, and she says she will feel a little more secure having the phone in case of emergency during a long drive.

But did she feel less secure without a phone nearly eight years ago when she was expecting Max?

No, she admits, she didn't. But cell phones weren't such an obvious purchase back then. Plus, they used to be so expensive.

The ubiquity of the technology has changed her conception of the accessories that go with responsible adulthood.

Now, if you are without a cell phone in certain situations, you have engaged in risky behavior.

On a sunny weekend, the dead zone is filled with walking, running, skating and biking people all in one way or another trying to figure out their evolving relationship with the technology.

Ask them about it and they use analogies: There are people who see the cell phone as a telephone, like the one at home--it should always work. Others compare it to an emergency flare or jumper cables you keep in the back of your car--great for extreme situations, but who needs jumper cables in the park? Others consider it a decadent and useless indulgence, like a fur or a third face lift--enough of this contemptible fad!

Susan Hackett, 38, and Richard Hagerty, 40, are walking their daughter, Claire, 7 months, in a jogging stroller. Hagerty doesn't know it, but Hackett has stowed a cell phone in a pocket of the stroller. Because of the baby, just in case.

Surprised when Hackett reveals the device, Hagerty tries to place a call as an experiment. They are Bell Atlantic Mobile customers, and the call goes through. So, they ask, why do we need antenna poles?

Fifteen years ago, there were no cell phones and everywhere was a dead zone. Today there are 1.3 million subscribers in the Washington area, according to the Strategis Group telecommunications consultants--a number nearly triple the population of the city itself.

The phone companies have been relentlessly erecting antennas ever since. Just as America's western frontier vanished at the end of the last century, the un-celled continent is about to disappear at the end of this one.

Potomac was a dead zone until Bell Atlantic erected a pole camouflaged as a tree in Avenel. Cell phone junkies will happily list numerous blocks and neighborhoods that are dead, some as small as 100 yards, but Rock Creek Park is the last major one, according to Bell Atlantic.

The dead zone is not lifeless. Three-fourths of the calls a reporter tried to place over the weekend were successful. After one failed attempt, he successfully placed a call from his cell phone to the cell phone of Bell Atlantic Mobile's spokeswoman, Audrey Schaefer. He got her voice mail, where he left a message asking how this communication could possibly be taking place.

Schaefer called back and left a message suggesting that calls may be easier to make during low-use periods, such as weekends. She also said anecdotal experience was not as reliable as measurements by the phone company's engineers that show that 44 percent of calls do not go through, or are interrupted once they begin. The dead zone foils thousands of Bell Atlantic Mobile customers' calls, she said. That includes calls attempted by people driving through the park during the week.

The wisdom of wiping out the region's last big dead zone at the cost of two antenna poles mandated by Congress has been actively debated on themail@dcwatch, an e-mail discussion forum on D.C. affairs. Most correspondents have damned the incursion, but some, such as Stan Wellborn, 54, who lives near the park, think it's time for the whole city to be covered.

Twice since Wellborn has had a cell phone, he has needed it to call for help during car trouble on highways in the rain or at night. Now he wouldn't feel right on such journeys without his phone.

But no, he says in an interview, he didn't feel less safe driving the same ground in his pre-cell phone days. That's the funny thing about a new technology. It changes perceptions of reality, which is the same thing as changing reality itself.

"You had a vacuum you didn't know was there," Wellborn says in an interview. "Suddenly cell phone technology comes along and fills the vacuum and you can't breathe without it."

This is a familiar process, according to those who have studied the invention and adoption of new technology.

"Once we bite the apple of knowledge, we cannot unbite it," says Amitai Etzioni, a professor of sociology at George Washington University.

In 15 short years, the cell phone has progressed from that initial stage when people speculate--usually incorrectly--about how a technology will be useful, to the point where laws are proposed to help make it ubiquitous.

"We didn't know 15 years ago that when we went to the grocery store we wanted to have our telephone with us," said Wendell Cochran, associate professor of communications at American University. "Where in the beginning you couldn't imagine what it was for, now you can't imagine life without it."

Jim McGrath, 48, has been an avid cell phone user since the beginning. He paid $2,700 for his first big clunky phone, and he knew what it was for immediately: to make calls for his commercial real estate business as he drove around and around the area. Now he talks 1,500 minutes or more a month on his cell phone--or at least 25 hours.

Today he is roller-blading in the park. He didn't bring his phone: He doesn't want to fall and land on it. He's seen it happen too many times.

But he is all for constructing the antenna poles, provided any company will be able to use them, so more won't have to be built.

Then he won't have to dodge the park in order to stay in touch. "It's a pain," he says. Recently he showed a client a building at the Navy Yard in Southeast Washington, and next they had to drive to Kensington. McGrath was going to cut through the park, but the man asked him not to, because he wanted to make business calls.

McGrath skirted the dead zone by driving up North Capitol. It took 20 minutes longer. But the conversations could continue uninterrupted.

CAPTION: Rob Christopher-Strayhorn finds a stronger signal for his cellular phone while watching his dog, Buddha, in Rock Creek Park.

CAPTION: Richard Hagerty, of Bethesda, uses his cellular phone while hiking with his family in Rock Creek Park.