In one of the more cinematic moments, people familiar with the case said, Mr. Seagal told investigators that in February 2001 he was visiting Mr. Nasso and his brother Vincent Nasso, also a reputed Gambino associate, in Brooklyn when he was ordered into a car to accompany both brothers and another reputed Gambino associate later charged in the case, Richard Bondi. After a switching of cars to throw off any pursuers, the journey ended at the Gage & Tollner restaurant in Downtown Brooklyn, where Anthony Ciccone, a reputed Gambino captain known as Sonny, and Primo Cassarino, a reputed family soldier, were waiting in a back room. It was here, people familiar with the case say, that the threat was made.

Not long afterward, people close to the investigation said, a tape recorder in one of the prime bugged locations, Brioso, a restaurant in Staten Island, picked up Mr. Ciccone and Mr. Cassarino chortling over scaring Mr. Seagal. ''They were laughing about it, saying it was right out of the movies and 'if we only had guns in our belts, it would be really good,' '' said a lawyer who heard the tape.

A month later, Mr. Seagal told investigators, he was visited unexpectedly at his home in Los Angeles by Julius Nasso, Mr. Ciccone and Mr. Cassarino, and that he subsequently paid Mr. Ciccone $700,000 through Mr. Nasso.

People familiar with the case said investigators were still trying to trace the money and learn more about the circumstances under which Mr. Ciccone would be demanding money from Mr. Seagal. But in a court argument last month, prosecutors said the two men and the Nasso brothers were seeking to use Mr. Ciccone's position in organized crime to force the extortion victim -- who has not been named in court but has been identified by all sides as the actor -- ''to either pay money or include J. Nasso in the individual's film projects.''

One of the 2,200 tapes recorded, the government said, captured Mr. Ciccone instructing Julius Nasso to demand $150,000 a film from Mr. Seagal. Another obscenity-laced tape excerpted in court, it said, depicted Mr. Ciccone ripping into Julius Nasso for supposedly using Mr. Ciccone's name to help collect money to pay film investors -- but without sharing the proceeds with Mr. Ciccone.

Another tape, people in the case said, recorded Mr. Nasso asking, and getting, Mr. Ciccone's permission to file suit against Mr. Seagal.

In a court hearing this week, Judge Fredric Block in Federal District Court in Brooklyn called the taped evidence against Mr. Cassarino so compelling that it was likely to result in his conviction.