With the information given by Ginevra, Luca and Lara go to the pharmacy to find out about recent sales of two drugs. When combined, the drugs are fatally poisonous. That same day the funeral takes place and the whole town is there. Manara takes advantage of this to look for new suspects.

An important new element in the investigation comes into play: some romantic letters found at the victim's house. Lara is comparing the handwriting to that of the note found next to his dead body.

Commissioner Manara and Inspector Rubino figure out who wrote the love letters and Lara conducts the appropriate interrogation.

In the presence of Ginevra who has come to thank both Lara and Manara for saving her reputation, they look once again at the painting of Lorenzo. A detail gives them the key to finding the murderer!

At this point the murderer is easily discovered and just as easily confesses. The evening of the murder gets revisited and all previous doubts vanish. But what's to become of the killer?

Although Commissario Manara's has resolved the case, his unorthodox methods are unacceptable to his superior, who threatens to have him transferred to the hinterlands of Sardinia.

In the end, Lara decides that Luca Manara isn't such a bad commissioner after all. She might even tell him that to his face... sooner or later.