Martin F. Dardis, 83, whose investigative skills connected the Watergate burglars to President Nixon’s Committee to Reelect the President and who also brought down drug smugglers, gun runners and embezzlers in 1970s-era Miami, died of vascular disease May 16 at a nursing home in Palm City, Fla.

A legendary character in the international criminal world of South Florida, Mr. Dardis was the chief investigator to Dade County’s state attorney Richard E. Gerstein and, later, Janet Reno. He went undercover to break up drug rings in the late 1970s and was forced to flee the state for almost 20 years as a result of death threats. He became an investigative reporter for Sports Illustrated magazine, cracked the Pete Rose gambling scandal and co-wrote a book about the influence of money in the National Basketball Association.

“He was dogged, determined and pursued the objectives of whatever he was after with an intensity that was remarkable,” said former attorney general Janet Reno. “He was just a very determined person who understood human nature and was tremendous. I found him to be really committed to civil liberties.”

In his most famous case, Mr. Dardis was tipped off to a Miami bank’s role in the June 1972 burglary of the Watergate offices of the Democratic National Committee. By tracing the sequentially numbered $100 bills found in the burglars’ pockets, he learned that one accused burglar, Bernard Baker of Miami, had deposited a check endorsed by Kenneth H. Dahlberg, he told then-Washington Post reporter Carl Bernstein.

Dahlberg, the Midwest finance chairman for the 1972 Nixon reelection campaign, subsequently told Post reporter Bob Woodward that the check came from campaign contributions and that he didn’t know how Baker had gotten it; Dahlberg had given the check to either the national committee’s chief fundraiser or its treasurer.

That was the first big break in what came to be known as the Watergate scandal.

Mr. Dardis didn’t like how he was portrayed in Woodward and Bernstein’s book, “All the President’s Men,” or in the subsequent movie, in which his character was played by actor Ned Beatty. Mr. Dardis complained that the movie made him look like a buffoon -- and a badly dressed one, at that.

At the 20th anniversary of the Watergate break-in, Mr. Dardis told the Miami Herald: “I was a guy who always thought my country could do no wrong. But I have been suspicious of federal agencies ever since. I can’t help it. To this day it bothers me. I was embarrassed for the country.”

He was born in Endicott, N.Y., and, with an eighth-grade education, left home to ride the rails. The 16-year-old lied about his age to enlist in the Army and spent the next eight years at war. He fought in the Battle of the Bulge and rescued one American flier from behind enemy lines. The pilot, who mistook him for a German and almost shot him, was none other than Kenneth H. Dahlberg, who became the Republican fundraiser from Minnesota.

Mr. Dardis and his companions, pinned down on their half-track trucks along the Arlon-Bastogne road and under bombardment, shot down two German planes with 37mm cannons and 50-caliber machine guns. By the time they got back to headquarters, they had missed the awarding of Silver Stars. Mr. Dardis rectified that 46 years later, when the evidence he painstakingly collected and presented to the Pentagon resulted in Silver Stars for the members of his unit. The award guarantees his burial in Arlington National Cemetery. He also was awarded a Bronze Star and two Purple Hearts.

After the war, he worked as a police officer in New York and Florida until going to work for the Florida attorney general in the 1960s. He moved to the Dade County state attorney’s office in the mid-1960s.

His work was central in prosecuting the most outrageous criminal conduct during a period of deadly crime sprees. Edward Carhart, the principal deputy prosecutor in the state attorney’s office at the time, called Mr. Dardis “the world’s greatest investigator.”

In the late 1970s, he went undercover, posing as a crooked cop in a cigarette smuggling operation. One thing led to another, and the case ended up bringing down a drug ring with annual sales of $500 million. Threats that the experienced investigator judged credible drove him and his family out of Miami, all the way to Upstate New York and his hometown of Endicott.

He worked for Sports Illustrated from about 1980 until last year. He co-wrote “Money Players: Days and Nights Inside the New NBA” (1997), a book that revealed players with gambling debts, point-shaving scandals and the effect of big money on the sport. He returned to live in South Florida in 1997.

Three of his marriages ended in divorce. Survivors include his wife of 42 years, Barbara Dardis of Palm City, Fla.; and six children.

As Mr. Dardis aged, he began to think more about the war and the small town where he was born. One of his daughters, Erin Dardis of Miami, said he spent years raising money to build a monument in Endicott for those killed in U.S. wars.

“It was so much work, so much effort. He really loved it for so long,” she said. “It was one of his most favorite places in the world. He’d go stand there with a rag and clean it off until it shone.”