MOSCOW—He operated under cover with a single false name on two continents for 34 years, through part of the Cold War and beyond. He served spymasters in Moscow who reward such steel-jawed endurance with quiet adulation.

In Peru he was Juan Lazaro the karate black belt, the news photographer, the guy who married the star TV reporter. After the couple moved to New York, he became Juan Lazaro Ph.D. and adjunct professor of political science. At home in suburban Yonkers, he was the doting father of Juan Lazaro Jr., a talented young pianist.

No one suspected until he was arrested by the Federal Bureau of Investigation, unmasked as Mikhail Vasenkov and sent home in the much-publicized U.S.-Russia spy swap a month ago.

Prime Minister Vladimir Putin feted the 10 deported agents, including femme fatale Anna Chapman, led them in patriotic Soviet songs and promised them decent jobs and a "bright life" in the motherland.

But the senior spy among them says no thanks. In a plot twist rare in the annals of espionage, he wants his Juan Lazaro fake identity back.

There's only one problem. The real Juan Lazaro died 63 years ago in Uruguay at age 3, a relative says. The spy used the dead toddler's birth certificate to build a persona.

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