In 1958 Danish diplomat Povl Bang Jensen was fired by the UN.
He'd worked as part of a special UN committee investigating the events of the Hungarian uprising.
Fearing their names would be leaked to the Russians he'd refused to hand over to his superiors at the UN the names of 81 witnesses to the Hungarian revolution.
A year later Bang Jensen's body was found in a New York park.
He had been shot in the head.
The Hungarian philosopher and playwright Andras Nagy was born in 1956 and has spent the last 13 years on a personal quest to clear up the mystery of Povl Bang Jensen's death.
Was it suicide? Or was he killed by Soviet agents?