THE INVESTIGATION, which Weiss describes as an “Oratorio in Eleven Cantos,” is draw from the Auschwitz Frankfurt trials, which were held in 1963, 1964, and 1965. Each canto focuses on specific a subject discussed at the trials. It requires a cast of twenty-eight men and two women. The roles include a Judge, a Counsel for the Prosecution, a Counsel for the Defense, eighteen defendants, and nine witnesses (including the two women.) Although the materials has been (obviously) edited for length, these are in fact the words of the accused, the witnesses, and the legal representatives at the trials.