A trial that some have dubbed the "Romanian Nuremberg" is set to open in Bucharest, with the head of a brutal communist-era labour camp, known as the "prison of silence", charged with crimes against humanity.
Alexandru Visinescu, 88, will face the court on Wednesday, accused of running an "extermination regime" at the notorious Ramnicu Sarat prison in the east of the country, which he headed from 1956 to 1963.
Rights activists hope Visinescu's trial will be the first of many, with 35 other former communist officials in prosecutors' crosshairs.
"This trial is particularly important, because for the first time an instrument of communist terror will face justice," said Radu Preda, head of the Institute for the Investigation of Communist Crimes and Memory of the Romanian Exile (IICCMRE).
"Without hyperbole, this amounts to a Romanian Nuremberg," he said, referring to the famous trials of Nazi leaders in Nuremberg, Germany, after World War II.
Visinescu says he is innocent and that he was only "obeying orders." If convicted, he faces life in prison, the AFP news agency reported.
The trial comes a quarter century after the downfall of Nicolae Ceausescu, who was executed, along with his wife Elena, on Christmas Day 1989, following an impromptu trial in which they were convicted of genocide.
We must personalise evil, otherwise it risks becoming an abstraction.
Most communist-era officials went unpunished. Although a few top leaders were also convicted of genocide, many later saw their charges reduced and were later released on health grounds.
But pressure has mounted for a true accounting of the regime's crimes, which included the imprisonment of more than 600,000 dissidents from the late 1940s onward.
A first complaint by the IICCMRE in 2006 against 210 former prison guards was rejected by prosecutors.
But in 2013, new prosecutors indicated they were finally prepared to listen, accepting a fresh demand for Visinescu and others to go on trial.
Public response to the trial has been muted, amid nostalgia for the communist era and disillusionment with the country's entry into the European Union in 2007.
For many victims, any trials would come too late, since most of the accused are already in their eighties.
But historian Adrian Cioroianu says that what matters is "that these crimes are punished and that the truth is re-established."
Preda, at the IICCMRE, also believes it is never too late to seek justice.
"We must personalise evil, otherwise it risks becoming an abstraction," he said.