Tear Jerker / A Haunting in Venice

• The opening reveals that years after the last movie, Poirot now lives in Venice alone—with only his bodyguard for occasional company; regrew his mustache and now no longer takes cases—which would also mean that his potential relationship with Salome Otterbourne also either fizzled out or didn't last.
• The story about the orphans. They were cared for by the doctors and nurses of the orphanage only for them to be abandoned and eventually die. Later it is revealed that many of them died in the basement, their bodies never found and left to rot, with the canal water eventually coming in and flooding the basement. There is even a massive basket full of their toys.
• Alicia's backstory before and up to her death. She was happily engaged with Maxime, only to break up with him when she found out he was (initially) only marrying her for her lucrative inheritance from her mother Rowena. Upon returning to her childhood home, her own mother poisoned her with hallucinogenic honey to keep her under her thumb which caused her to suffer from agonizing pain and horrifying hallucinations until she was accidentally fed a lethal amount of said honey. The kicker? Maxime eventually realized he loved her more than her fortune and sent letter after letter begging for her to take him back, but thanks to Rowena's interference Alicia never received them. Alicia spent her last moments suffering, believing Maxime never truly loved her while never knowing her mother was the one keeping her sick. It almost makes her Accidental Murder seem like a Mercy Kill.
• Maxime is brought to tears and clutching Alicia's toy rabbit after the truth of Alicia's horrible treatment and death is brought to light, having realized far too late that she truly meant everything to him.
• Poor Leopold just wanted to help his father and that is what caused him to blackmail Rowena. His blackmail triggers the entire mystery, leading to the deaths of three people including his own father.
• Leopold's father and his entire condition. He is shellshocked from the War, having been a part of the liberation of a concentration camp which turned into a SNAFU that resulted in some of the prisoners dying . This caused him to become so broken he can't even care for his son properly, something he is ashamed of. And then finally the woman he loves tells him she murdered her own daughter and she currently has his son, making clear if he doesn't kill himself right then she will kill his son.
• Mrs. Oliver lashes out at Poirot when it comes out that she was working with Mrs. Reynolds to trick him so she could write a book. She claims she made Poirot, that they aren't friends, and she has every right to use him as she did. While Poirot isn't harsh in saying goodbye to her and they part on speaking terms, simply saying he never wants to see his name in her books again, she is still upset her plan failed and curtly remarks she never wants to hear his name again.
• Poirot's bodyguard revealing he was in league with Oliver and Reynolds. It is clear he regrets his actions and Poirot doesn't turn him into the police for fraud at the end, but the latter makes clear he no longer has use for him, ending their friendship.
• While it's supposed to be a case of He's Back!, Poirot informing someone seeking his help that a family friend killed the man's father, mother, and brother and most likely will kill him is still depressing. One understands why Poirot lost his faith.
• Olga's horrified reaction to learning that she was the one who ignorantly fed Alicia the overdose of the hallucinogenic honey and directly dealt her the death blow.

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