A harried Warren Rich, looking as if he needed to be cleaned and pressed, tramped into the lobby of WRC television in Washington with some rumpled papers and an extra shirt under his arm. Rich, the Republican candidate for Maryland attorney general, rushed up to the hobby guard and said. "Hi, I need somewhere to change first."

"Well, who are you?" the guard asked.

Introductions were handled by a bystander and Rich was hustled off to put himself together for the first televised debate between the candidates in Washington.

A few minutes later, Stephen Sachs, in a perfectly tailored pin-striped suit, strode in accompained by his driver, his pollster and his campaign manager.

"Hi, I'm Steve Sachs," he said, extending his hand to the guard. The man grasped it and immediately called inside to tell the producers that the Democratic candidate had arrived.

The scenes were made to order for a movie about the quintessential front-runner and the reluctant challenger.

Sachs, a Yale graduate and former corruption-fighting federal prosecutor, has a burning desire to be a politically independent attorney general, "the people's lawyer." Bucking Maryland tradition by refusing to join a gubernatiorial ticket, he set out in 1976 on a two-year quest for the job, backed by a loyal campaign crew and ultimately bolstered by more than $330,000 in contributions.

Rich, an environmental lawyer and self-proclaimed recluse who says he hates politics and campaigning, plunged into the race in the GOP primary at the last moment in July only because he dislikes Sachs and absolutely abhors Sachs' view of the office.

The two men met for the first time at a consumer forum during last summer's primary. Sachs introduced himself and extended his hand. Rich smiled, said, "I know who you are, Mr. Sachs," and ignored the offer of a handshake. Asked about the incident, Rich shrugged and said, "I don't like him."

"It was partly Warren's sense of humor . . . part his attitude that you psych out your opponent," said a lawyer who was present.

That attitude, which Rich also takes into the courtroom, apparently served him well during seven years as an assistant attorney general specializing in environmental matters. He had an "extraordinary string of successes in lawsuits he brought for the state," said former deputy attorney general and Democrat Henry Lord.

Rich closed down strip mines; halted a vacation-home development whose runoff was polluting thePotomac; sparred with public officials in Camden, N.J., and Philadelphia, to stop sewage dumping that was damaging Maryland's ocean waters, according to Lord.

When Rich resigned last February to go into private practice, a state natural resources official was quoted as saying that on one occasion "we were really on very shaky legal ground, but Warren scared the other attorney so bad, we settled out of court."

Rich tried the same technique on Sachs, but it didn't work.

In the WRC debate, the 39-year-old Rich spoke at length, vilifying Sachs and refusing to let him get in a word. "Now that he's foaming at the month, he can have a chance," Rich finnally concluded.

Sachs, who had sat through the onslaught with his hands folded on a comfortably cross leg, quietly responded: "I'd like to say as calmly as I can in the face of a tantrum . . ." and then made his point.

The imperturbability is apparently part of the package that makes the 44-year-old Sachs what colleagues describe as "an extremely talented lawyer, a relentless investigator and one of the most skillful cross-examiners to enter a courtroom."

The boyish-looking Sachs homed those skills during seven years in the Office of the U.S. Attorney for Maryland, three of them as its chief. During that period in the 60s he prosecuted figures in the Maryland savings and loan scandals and numerous public officials.

Although he says he enjoyed his work the past eight years as a criminal defense lawyer and civil litigator in his native Baltimore, "the happiest years of my professional life were as a U.S. attorney and an assistant . . . serving the public interest."

Both he and Rich have forcefully argued their concept of theoffice they are seeking. Sachs has promised to bring to the office a vigorous new law enforcement approach in everything from the handling of consumer complaints to the rooting out of official corruption. Rich, who is from Easton, has argued that the attorney general's major role is to see that Maryland law is carried out effectively and economically by the governor and the state departments.

Sachs, true to the meticulous way he handles cases, is cautioning supporters not to get cocky because he is ahead in the polls and he is keeping up a nonstop campaign schedule.

Rich, predicting that "the vote will be closer than you think," is hustling around the state too - without campaign buttons (someone forgot to order them) and with a $3,000 TV ad in the can, but no money to get it on the air.