Aladena "Jimmy the Weasel" Fratianno was an Italian-American mobster who became acting boss of the Los Angeles crime family before turning informant in 1977. Born in Naples, Italy, in 1913, he immigrated to the U.S. and became involved in organized crime, earning his nickname as a young fugitive in Cleveland. Over the years, he was convicted of robbery, extortion, and racketeering, spending time in prison before rising to a leadership role in the Los Angeles Mafia.

Fratianno had international criminal ties, including connections with Australian organized crime figures and involvement in smuggling operations. In 1975, he became co-acting boss of the L.A. crime family but soon found himself entangled in internal power struggles. Suspecting a plot against him, he turned government witness in 1977 after being implicated in the murder of Irish mobster Danny Greene. His testimony helped convict several high-ranking Mafia figures.

After entering the Witness Protection Program in 1980, Fratianno co-authored two books about his life before being expelled from the program in 1987. He admitted to participating in five murders and spent his later years in hiding. He died of natural causes in 1993.