Gray-haired, pale and immaculate in his neatly pressed prison uniform, Michele Sindona, 62, retains an aura of the multimillionaire banker and financial genius. Now serving a 25-year term in upstate New York for bank fraud in connection with the 1974 collapse of the Franklin National Bank, Sindona was for years a financial adviser to the Vatican. Though he still insists that he was framed in the Franklin affair by powerful Italian state banking interests who would not produce documents that would clear him, he readily admits to being deeply involved in the events that led to the downfall of Banco Ambrosiano and its late president, Roberto Calvi. In a mild, authoritative voice that occasionally erupted into impassioned Italian, Sindona spoke at length with TIME Correspondent Jonathan Beaty, sometimes disputing versions of the story that have emerged thus far and offering revealing glimpses of its protagonists. Some of the statements of Sindona, a convicted felon, are at odds with those of church officials, who deny any wrongdoing at all by the Vatican bank or its officers.

Sindona contends that he first met Calvi, then a junior executive with Banco Ambrosiano, around 1967. The two agreed that Calvi would act as inside man in a plan to gain eventual control over the bank and make it international.

Says Sindona: "Our goal was to buy control in Banco Ambrosiano." Sindona says that he first introduced Calvi to Archbishop Paul Marcinkus in 1971, the year the priest became president of the Vatican bank. Sindona strongly denies that he paid Calvi and Marcinkus a $6.5 million commission as part of a business deal in the early 1970s, as has been widely reported. Says Sindona: "I did give $6.5 million to Calvi, much more than that, but that was to buy shares of Ambrosiano and other stocks. None went to Marcinkus unless Calvi gave it to him." Sindona insists that Marcinkus was "greedy but honest."

Says Sindona: "He used the money [I.O.R. earned] to impress the Pope, to promote himself. With me he had every opportunity to propose a deal, to make personal money.

With me he never even brought up the possibility." But Sindona believed Marcinkus was "incompetent" in choosing Vatican investments. "He is a good bodyguard," quipped Sindona, "but no banker."

Why did not Pope John Paul II look more closely into his bank's affairs? "John Paul is not a financial man," says Sindona. "The people around him were afraid of Marcinkus' power." Sindona claims that Ambrosiano paid the I.O.R. some $20 million in fees and interest in 1981 alone. Sindona was critical of his carefully chosen colleague. Calvi, says Sindona, "had no interests, only money and power. He was no good at choosing other people. If counts or barons went to him, he was immediately impressed. Calvi was known for paying a lot of money in Italy. He was too generous. He paid enormous fees and commissions, always commissions. You know in Italy you don't stay in the high places unless you corrupt somebody."

Sindona also discussed his involvement with Calvi and other members of the Italian Masonic Lodge P2 in sending Banco Ambrosiano money to Latin America to support right-wing political causes. "Calvi financed newspapers for ideological reasons in Buenos Aires and Montevideo.

Money was given to political parties. But money to dictators and generals was sometimes under the table. Calvi feared his trips to South America because the Communists, the Cubans, knew that Calvi with [fellow P2 Members] Gelli and Ortolani were building rightist strength in South America. That was our goal." Sindona's more immediate goals involve fighting extradition to Italy, where he faces charges related to the collapse of his Italian banks. In the meantime, the former titan of international finance, the onetime owner of banks, hotels and construction companies spends his days worrying about whether he will obtain permission to install a bookshelf in his cell.