Murder in the Excelsior Hotel (1971)

This retro crime story revolves around a bottle of French cognac that was used to kill the charming Dana Matousová in a high-end Prague establishment. All the threads of the intricate case, which involves gambling and in which both the hotel staff and the guests, including a mysterious Persian diplomat, gradually fall under suspicion, are skillfully untangled by police councilor Vacátko and his colleagues. The intricate charade is mainly the responsibility of the hotel's manager, Hnízdo, who tries to preserve the hotel's reputation at all costs.