Between 1937 and 1938, Soviet leader Josef Stalin carried out his most severe purge in Georgia. Known as the Great Terror, thousands of political rivals, intellectuals and ordinary citizens were executed without trial and buried in mass graves. Dan Hardoon speaks to Levan Pesvianidze in Tbilisi, Georgia, whose grandfather Viktor and uncle Giorgi were both executed.(Photo: Viktor Pesvianidze with colleagues in Georgia in the 1930s. Credit: Levan Pesvianidze)