The camera focuses on an earnest-looking young man with tortoise shell glasses and a buttoned-down blue shirt.

"Hi, my name is Dan Perlmutter and I used to be an assistant U.S. attorney," he says. "But then I became a drug addict and I lost everything. I lost my career, my family, and finally my freedom. Then I spent 18 months in jail as a result of my drug addiction and it was the biggest mistake I ever made in my life."

Perlmutter, once a promising young prosecutor in the Manhattan U.S. Attorney's office, stole cocaine and heroin from an office evidence safe to feed his drug habit. He is the star of what could be described as the Justice Department's answer to the film "Reefer Madness": three videotapes prepared to accompany the launch of the department's controversial plan to test its lawyers and other employes for drug use.

The videotapes explain why the department will begin randomly testing its employes for evidence of drug use, outline the dangers of marijuana and cocaine, and assure workers that they have nothing to fear from the tests if they are not using drugs.

The tapes, which cost about $30,000 to produce, will premiere before department employes next month, when Justice officials hope to unveil their long-awaited plan to require workers to submit to random urine testing.

"They are an effort to educate, to persuade . . . that the program is needed," said department spokesman Patrick S. Korten, who supervised the production of the videotapes and serves as narrator.

There may be a lot of persuading to do. Some Justice Department lawyers are planning to sue to block the testing, which is expected to be limited to employes with security clearances or access to grand jury material, or having other high-responsibility duties.

"The tendency among a lot of people here, especially among the lawyers . . . is to assume that nobody in this department, of all departments, would ever get involved with drugs and that it is an insult to even suggest such a thing," Korten said. "This tape is designed to persuade them that is not the case."

Perlmutter, recently released from prison, agreed to serve as Exhibit A.

"If the Department of Justice had had a drug testing program in place before I started using, it certainly would have acted to deter me from ever starting on the road that I started on because I was very conscious when I started using of not getting caught," he says on the tape.

"All of us would like to think that it would never happen to us," Perlmutter tells his former colleagues. "I was certainly one of those people. But if you're not using, then it should not be something that bothers you, and if you are, it certainly will bother you, but it will probably end up helping you. And if you are not using, but may end up using, it may save your life."

Dr. Donald McDonald, President Reagan's drug policy adviser, paints the issue as one of patriotism and loyalty. "I guess what you have to ask yourself as a federal employe is, do you think this country has a drug problem?" he says.

"If you are like 80 percent of your peers, you're going to say 'Yes, I'm concerned about that,' and what the president is asking you to do is to help . . . . Nobody likes to be involved in this dumb business, but it is something that we have to do and should bring us to great reward."

Charles Schuster of the National Institute on Drug Abuse explains why it is particularly appropriate to test Justice Department employes. "In the Justice Department, there are people daily coming into contact with illicit substances through their work," he says.

"Sadly, we know that there will be those who will become involved with them and dependent upon them, and I think it is important . . . as a means of safeguarding people who are going to be in contact with these kinds of drugs, to have a urine testing program as an extra motivation to say, 'No, I could never experiment with this.' "

Part Two focuses on the particular dangers of marijuana and cocaine, the two most widely used drugs. "Cocaine is one of the most addictive drugs known to science," the narrator warns. "In laboratory experiments, animals given free access to cocaine select it in preference to food, water and sex -- until it kills them." On the screen, a dead rat lies on its side.

To the accompaniment of ominous-sounding music, statements flash on the screen ("Fact: One out of every six Americans between the ages of 20 and 40 uses illicit drugs . . . . Fact: "Most users of hard drugs start with 'gateway drugs' such as marijuana").

Part Three attempts to dispel worries that eating too many poppy seed bagels could result in a positive reading on a drug test. "There's no possibility that someone who has not used drugs will in fact come up positive through our system of drug testing," says one expert.

"These machines are so accurate, it's like a fingerprint," a laboratory worker adds.

Korten discounted suggestions that the tapes might receive a skeptical reception among the often cynical corps of federal prosecutors and other lawyers subject to testing. He said that the response "has been very positive" among senior agency officials who have seen the first videotape.

"We're not going to force anybody to watch it," Korten said. "We're going to tell them, 'We'd like you to come in and sit down and watch this.' It's not mandatory."