A CBS Newsman is murdered: "Who Killed George Polk?" A CBS News Radio documentary

On the 75th anniversary of the murder of CBS News correspondent George Polk, CBS News White House correspondent Steven Portnoy begins the network's first dive into the case in decades. Polk was in Greece to cover that country's civil war, a fight that pitted forces backed by Washington against communist guerrillas aligned with Moscow. 

Part I: "A CBS Newsman is Murdered"

The body of CBS News correspondent George Polk is found floating in the bay near Greece's Salonika waterfront. On the 75th anniversary of the murder, White House correspondent Steven Portnoy begins the network's first dive into the case in decades. Polk was in Greece to cover that country's civil war, a battle that pitted forces backed by Washington against communist guerrillas aligned with Moscow. He had criticized the right-wing authorities now charged with finding his killer. Shocked by Polk's murder, prominent journalists ask the father of the U.S. intelligence community to oversee the investigation. Gen. William "Wild Bill" Donovan identifies a suspect.

Part II: "The Show Trial"

After weeks of torture at the hands of Greek authorities, a fellow reporter goes on trial for the murder of George Polk. The dead man's teenage brother winces through the proceedings but William Polk's doubts about the suspect's guilt are stifled by the bullying of a legendary spymaster. Government documents show U.S. officials colluding with Gen. Donovan to keep American journalists in line as the show trial unfolds. Gregory Staktopoulos fights for justice. Another motive for the killing of George Polk emerges.

Part III: "The Cover-up"

Author Kati Marton lays out her theory of how George Polk was killed and by whom. Other experts weigh in. Portnoy looks at efforts U.S. officials undertook to explore a motive for George Polk's murder that never came up at the trial. Why did the U.S. government and American journalists not do more to press for justice in Polk's killing? What did a British press attaché have to do with Polk's disappearance? The communist leader Polk aimed to interview speaks to CBS "60 Minutes'" Ed Bradley. Journalism advocates explain why this 75-year-old story still matters today. Edward R. Murrow has the last word.

The full program airs on radio stations nationwide and SiriusXM's P.O.T.U.S. Channel 124 Memorial Day, Monday, May 29, 4-7 a.m. and 6-9 p.m. ET, and will post online on Friday at cbsnews.com/polk.