Leslie Nielsen, leading man and slapstick star

LOS ANGELES - Leslie Nielsen, 84, who traded in his dramatic persona for inspired bumbling as a hapless doctor in

Airplane!

and the accident-prone detective Frank Drebin in

The Naked Gun

comedies, died Sunday in Fort Lauderdale, Fla.

The Canadian-born actor died of complications from pneumonia at a hospital near his home at 5:34 p.m., surrounded by his wife, Barbaree, and friends, his agent, John S. Kelly, said in a statement.

Mr. Nielsen came to Hollywood in the mid-1950s after performing in 150 live television dramas in New York. With a craggily handsome face, blond hair, and 6-foot-2 height, he seemed ideal for a movie leading man.

Mr. Nielsen first performed as the king of France in the Paramount operetta The Vagabond King with Kathryn Grayson. The film - he called it "The Vagabond Turkey" - flopped, but MGM signed him to a seven-year contract.

His first role for that studio was auspicious - the spaceship commander in Forbidden Planet. He found his best dramatic role as the captain of an overturned ocean liner in the 1972 disaster movie The Poseidon Adventure.

He became known as a serious actor, though behind the camera he was a prankster. That aspect of his personality was never exploited, however, until Airplane! was released in 1980 and became a huge hit.

As the doctor aboard a plane in which the pilots, and some of the passengers, become violently ill, Mr. Nielsen says they must get to a hospital right away.

"A hospital? What is it?" a flight attendant asks, inquiring about the illness.

"It's a big building with patients, but that's not important right now," Mr. Nielsen deadpans.

When he asks a passenger if he can fly the plane, the man replies, "Surely you can't be serious."

Mr. Nielsen responds: "I am serious, and don't call me Shirley."

Critics argued he was being cast against type, but Mr. Nielsen disagreed. "I've always been cast against type before," he said, adding comedy was what he'd really always wanted to do.

After the success of Airplane!, its creators, Jim Abrahams, David Zucker, and Jerry Zucker, cast their newfound comic star as Detective Frank Drebin in a TV series, Police Squad!, which trashed the cliches of Dragnet and other cop shows. ABC canceled it after only four episodes.

"It didn't belong on TV," Mr. Nielsen later commented. "It had the kind of humor you had to pay attention to."

The Zuckers and Abraham converted the series into a feature film, The Naked Gun, with George Kennedy, O.J. Simpson, and Priscilla Presley as Mr. Nielsen's costars. Its huge success led to sequels The Naked Gun 21/2 and The Naked Gun 331/3.

His later movies included All I Want for Christmas, Dracula: Dead and Loving It, and Spy Hard.

Mr. Nielsen was born Feb. 11, 1926, in Regina, Saskatchewan.

He grew up 200 miles south of the Arctic Circle at Fort Norman, where his father was an officer of the Royal Canadian Mounted Police.

The parents had three sons, and Mr. Nielsen once recalled, "There were 15 people in the village, including five of us. If my father arrested somebody in the winter, he'd have to wait until the thaw to turn him in."

The elder Nielsen was a troubled man who beat his wife and sons, and son Leslie longed to escape. After he graduated from high school at 17, he joined the Royal Canadian Air Force, though he was legally deaf (he wore hearing aids most of his life).

After the war, Mr. Nielsen worked as a disc jockey at a Calgary radio station, then studied at a Toronto radio school operated by Lorne Greene, who went on to star on the TV series Bonanza. A scholarship to the Neighborhood Playhouse brought him to New York, where he immersed himself in live television.

Mr. Nielsen also was married to Monica Boyer, from 1950 to 1955; Sandy Ullman, 1958 to 1974; and Brooks Oliver, 1981 to 1985.

Mr. Nielsen and his second wife had two daughters, Thea and Maura.