Boris Morros

Boris Morros (January 1, 1891 - January 8, 1963) was an American Communist Party member, Soviet agent, and FBI double agent. He also worked at Paramount Pictures, where he produced films as well as supervising their music department.

Morros was born in Saint Petersburg, Russia. He emigrated with his family to America in 1922. In 1934 he was enlisted as a Soviet spy, following which time Vasily Zarubin became his first contact in 1936.

The mysterious "Mr Guver" letter, sent to FBI Director J. Edgar Hoover in 1943 from an anonymous source, who is now widely believed to be KGB Officer Vassili Mironov, named Morros as an agent working with Soviet intelligence and identified Elizabeth Zarubina as Morros' contact.

In December 1943, Zarubin drove with Morros to Connecticut, where they met with Alfred Stern and his wife Martha Dodd Stern. Soviet intelligence wanted to use an investment from the Sterns in Morros' sheet music company to serve as cover for espionage. The Sterns invested $130,000 in the Boris Morros Music Company.

In 1947, Morros became a counterspy for the FBI. He reported on Jack Soble and members of the Soble spy ring, while also passing low-level secrets and misinformation back to Moscow. Morros' codename in Soviet intelligence and the Venona files was "FROST."

In 1960, Man on a String, a feature film loosely based on Morros' adventures as a counterspy, was released. Ernest Borgnine played Morros, who co-wrote the screenplay.

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