Sign of the Cancer (1967)

When Dr. Hahn is found murdered in the hospital’s inspection room, investigators question several suspects: his colleague and longtime lover Dr. Marie Nováková (whom he cheated on with nurse Jiřina), the nurse herself, Dr. Petera (whose career he stymied), a senile patient named Zima, and the inept clinic head. As police sift through truthful and deceptive testimonies, complex professional rivalries and personal entanglements among the hospital staff come to light.