The ancient Peugeot has been pulled from the swamp. The trench coat has been hung up for good and replaced by a knock-off. The middle-aged guest stars have been pushed aside in favor of a couple of kids.

Everything's in place for a new episode of "Columbo."

Tonight at 9 on ABC, Peter Falk shuffles on for another duel of wits in "Columbo Goes to College." Robert Culp guest stars, but viewers familiar with the Columbo formula will be surprised to know that he isn't the killer.

That honor, so to speak -- and we're not giving anything away here, since the Columbo formula calls for full disclosure of the killer before the second commercial -- the killers in this episode are a pair of college students whose theft of a final exam is discovered by a professor. Fearing nasty consequences, they resort to the ultimate solution.

And they would seem to have an air-tight alibi: The students, played by Cooper Redman and Justin Rowe, commit the murder while sitting in class -- where the guest lecturer is none other than Lt. Columbo.

"They've conceived of a murder that's so clever that the thing that breaks the case is a fluke," said Falk. "They're sitting in the classroom in a criminology class at a university; Columbo's been invited there and is answering questions. The prof, for some reason, gets up and leaves the class and goes down to the garage to get his car to go some place, and as he goes to his car he's shot. So the murderers are sitting right there in front of me at the time of the crime."

It is fitting that Peter Falk should slide between the third person and the first when he discusses Columbo. He has lived with the part, off and on, for nearly a quarter of a century.

In conversation, he sounds like Columbo, speaking deliberately with pauses thrown in. You learn to wait for the rest of the sentence from Peter Falk. Just as you learned to wait for the final word from Columbo as he turned to leave his quarry, the prime suspect, unchallenged. "Oh, by the way," he might say, "I hate to keep bothering you, but why did you kill your wife?"

This week, Columbo takes on the college students in a different sort of duel of wits.

"Ordinarily, Columbo would go up against their parents," said Falk, referring to the usual "Columbo" killer. "They're products of the '80s. There's a lot of loose dough around. They only know fame and success. They're very materialistic. And very smart."

Much of the by-play between the homicide detectives and the criminology students has them picking on the lieutenant, with him taking their jibes as compliments.

"After the initial investigation, the kids invite Columbo out for a drink. I don't know if I can do that because I'm involved in a murder investigation. But I do find out one thing ... I forget the details ... The one tiny thing I find out prompts me to go to the college hangout. They're all there, and that begins the relationship with all the kids."

Then begins the baiting. The kids, who tool around in a Porsche, praise Columbo's faithful 1950 Peugeot.

"I say, 'Yes, I get offers for it every day.' They say, 'What about your suit? You get offers for that too?' We're both playing games with each other."

The objects of the students' derision have been objects of admiration and amusement for TV viewers since 1968. There's the halting manner, seemingly as much Falk's as it is Columbo's. The rumpled suit, shirt and tie -- clothes that the show's creators said Falk wore exclusively for the entire 1971-78 run of "Columbo" as a weekly series.

And there's the car and coat: the trench that was marked for destiny on a rainy day in New York; the car, once a twin, that survived sale and salvage.

"It's the same car we've used since the start of the series," recalled Falk. "They sold it when they shut down the series for a while." Then "Columbo" was brought back as a part of an ABC mystery rotation and now as a series of free-standing TV movies.

"They put out a search when the series resumed," said Falk. "There were two cars, the original, then they got a backup. They found both of them. One was in a swamp and was beyond redemption. The other had to be fixed up. If you've got a good eye, you can see the color's bleached out more than it used to be."

There are backups for the trench coat too, but the original was a part of the series from the start until Falk put it in mothballs.

"I was wearing the original trench up to last year," he said. "I bought it in 1967 on 57th Street in New York, between Madison and Park, on the north side of the street. It was raining and I ducked in. I was on my way to England. When we went to do 'Columbo,' I took it out and said we'll wear this. It's a good thing to wear. It got so frail, I put it in the closet. I was afraid it would fall apart. It's threadbare. I used to joke I had to put out a saucer of milk for it every night."

The career scenario that took Peter Falk to "Columbo" followed anything but the usual aspiring-actor's path. The native New Yorker started out as a cook in the merchant marine, and when he returned to school, it wasn't for a drama degree. He earned a bachelor of arts degree from the New School of Social Research and a masters in public administration from Syracuse University. Naturally, that led to a job as an efficiency expert with the state of Connecticut.

Along the way, he had dabbled in acting. But finally he took a serious turn to drama. He won praise off-Broadway in "The Iceman Cometh," and was on his way to a career on stage and film. In 1960, he was nominated for a supporting-actor Oscar for his portrayal of a mobster in "Murder, Inc.," and again the next year for his part in Frank Capra's "Pocketful of Miracles." Two years later he won an Emmy in the role of the truck driver in "The Price of Tomatoes."

Four more Emmys would follow, all for playing Columbo.

Making the move from the East Coast to the West, Falk contracted what he once called golf disease, but not to the degree of that long-sufferer Bing Crosby. Good thing.

In the late '60s, the "Columbo" creators, Richard Levinson and Williams Link, were looking to revive the character who had been played in earlier incarnations by Bert Freed and Thomas Mitchell. This time, Lee J. Cobb was said to be a candidate. But the main contender, Falk recalled, was Crosby.

"I have a dim memory," he said in Columbo fashion, "of sitting on a couch, in my house in the foothills, reading the script, liking it and the character a lot. And I have a memory of going some place -- we're going back a lot of years -- I don't know if it was an agent or who, said it was taken and Crosby had it, that it was taken.

"I do remember this: An agent called and said that Crosby was scheduled to play golf and couldn't turn it down to go over and talk to Link and Levinson. He did love golf. I play too, but I went over and talked to them. Let's see. This is 1990. When the hell was that? That was 1966, 1967."

Falk debuted as Columbo, the policeman with no first name, in "Prescription: Murder" in February 1968. A second Columbo TV movie, "Ransom for a Dead Man," aired in March 1971. That fall, it became a series, running through 1978 (with no fresh episodes during the '76-'77 season). Toward the end of the show's run on NBC, Falk was divorced from the mother of his two daughters and married Shera Danese, who at one point played a villain in the series.

The Columbo persona was established right from the start.

"I remember when we did the season's pilot, with Lee Grant in a kidnapping case," said Falk. "The FBI was involved. There was a scene in Lee Grant's living room, and the FBI guys were there. When I arrived, the main character, people paid attention to me. And I didn't like that. I thought, not only is it more amusing but more accurate that when the local guy arrives they ignore him."

In the reconfiguration of the scene, Columbo was on the periphery.

"When Columbo arrives, he can hardly hear what the guy is saying because he has to stand in the back, stand on tiptoes to even see the evidence. And the FBI guys are even a little annoyed at being interrupted. It's funny when the smartest guy in the room can't even see the evidence and has to whisper, 'What's he saying?'"

Falk didn't start out to be amusing. Despite the wry, shuffling presence of Columbo, in TV movies, series and reruns, for more than two decades, he still goes for the dramatic first. And despite his identification with one character for roughly a third of his 63 years, he's found quick identification in another comedy role as well.

"I never saw myself doing funny things," he said. "I get a little nervous when it's supposed to be funny. If there's anything I hate is a guy trying to be funny when he's not. On the other hand, I can't stand watching characters that are earnest."

So you can imagine his quandary when he found himself on the set of the 1979 theatrical film "The In-Laws," faced with doing a funny scene with Alan Arkin.

It involved the two men being peppered by gunfire while trying to scurry for cover. Falk advises Arkin to run in a zig-zag, snake-like fashion, in a serpentine pattern to make himself a harder target. When Arkin makes a straight dash for cover, Falk insists that he go back -- facing gunfire yet again -- and do it right. "Run serpentine!" he encourages. "Go serpentine!" It's an extremely funny scene in the viewing, if not in the telling. But Falk feared it would not stir a chuckle.

"I told Arkin, 'I suppose you think this is funny,'" recalled Falk. "I thought it was silly. When we went to do it, he loved it so much, he thought it was so amusing, that as he was doing it -- he could do it all day, forever. And while we were doing it, I got such a kick out of looking at him, looking at him loving it, that it made it fun to do.

"Now, people yell at me from taxis, in airports, 'Serpentine! Serpentine!'"

That is, of course, if they don't yell, "Hey, Columbo!"