Using the authentic script taken from the only surviving transcript recorded during the meeting, the film delves into the psychology of Nazi officials involved in the "Final Solution of the Jewish question" during World War II.

On 20 January 1942, Nazi German officials hold a conference at a villa in Wannsee, a wealthy district on the outskirts of Berlin, to determine the method by which they will make Germany's territory free of Jews, including the occupied countries of Poland, Reichskommissariat Ostland, Czechoslovakia and France.

Chairing the meeting is Reinhard Heydrich, chief of the Reich Security Main Office, who states he has been given a mandate in the form of a directive from Reichsmarschall Hermann Göring to achieve a "complete solution of the Jewish question."

On reconvening, Heydrich reveals in frank detail the policy that had already been decided before the meeting convened: the wholesale extermination of Europe's Jewish population using gas chambers and ovens to incinerate the bodies.

SS-Obersturmbannführer Adolf Eichmann then reveals that the SS has been building extermination camps at Belzec, Sobibor and Treblinka, and making preparations for the "Final Solution" under the noses of Germany's civilian bureaucrats.

Throughout the meeting and over refreshments attendees raise other side issues, reflecting the interests of their respective work areas, including concerns that cholera and typhus could break out from the overpopulated ghettos in Poland.

Most of the members either died during the war or were arrested immediately after; two, Josef Bühler and Karl Eberhard Schongarth, are convicted by Allied military tribunals and executed, and the others acquitted to live a peaceful life in postwar West Germany.

The final card before the credits reveals that Luther's copy of the Wannsee minutes, recovered by the US Army in the archives of the German Foreign Office in 1947, was the only record of the conference to survive.

Callendar also notes the presence of distinct groups of various ranking officials (and their conflict objectives) which underscores the Holocaust's emergence as a result of competing interests among different governmental agencies.

Branagh's portrayal was challenging not only by the difficulty of delivering lines but also by the absence of discernible motivations or upbringing factors explaining Heydrich's chilling readiness to perpetrate genocide on an unprecedented scale.

Branagh reaffirmed a recurring theme of the film, emphasizing its commitment to historical accuracy over sensationalism or star power, underscoring the importance of authentically recounting this harrowing chapter of history.

Steinweis also juxtaposes Conspiracy with its 1984 German predecessor, Die Wannseekonferenz, suggesting that the earlier film may offer a more historically accurate depiction by providing a more detailed examination of the killing process.