Major spoilers abound.
Fridge Brilliance
- Throughout the game's chapters, Anna is shown to have a knack for fixing things, picking up locks, and defusing bombs. She reveals the source of these skills in the beginning of The Heir; while fixing Osvald's watch, she tells that her grandfather, who was a clockmaker, taught her how to fix most common problems. The Dada Killer further reveals that she grew up working in a repair shop.
- In Deadly Snowstorm, Anna deduces that Father Lenz is involved with the cigarette boxes stored in the cellar due to him asking if she discovered anything suspicious besides finding the body of Dr. Hartmann outside the cellar. She has another reason to suspect as much: you can find the business card of Father Lenz on the cigarette boxes.
- It's several times stated that the wheelchairbound Dr. Hartmann couldn't go to Hotel Reger's second floor. So how is he able to deliver messages to Anna and Walter's rooms that are both on the second floor? Simple: by having Otto deliver the messages. As for why he'd encode the messages, he wants to show Anna and Walter the smuggled cigarettes stored in the cellar. Since he has reason to suspect that Otto is involved and could be more dangerous than he appears, given Professor Kinsky and Ulla's mysterious deaths, Hartmann cannot risk Otto finding out that he's on to him. It also explains why Dr. Hartmann gives vague answers to Otto's questions about where he was around Ulla's time of death.
- Why does Anna speak to the remaining guests of Hotel Reger about what motives each of them could have for killing one of the murder victims, only to reveal that Claudia was behind them all? She's deliberately stalling time for the police to arrive before Claudia can go packing and escape.
- Why would Claudia and Helmut's assassin try to frame Professor Clark for their murder? Perhaps the Nazi Party intends to have the professor locked up so that they can offer to pull some strings and get him out of jail if he agrees to work for them.
- Osvald is established to be Anna's friend, yet she becomes secretive with him about her investigation. Silvia gives her a reason to be careful about what she chooses to tell Osvald; Osvald acts surprised when it turns out that Silvia had secretly boarded the train, but Silvia tells Anna she thinks Osvald noticed her despite her efforts to remain inconspicuous. Because Osvald lied to Anna, she knows she must consider him a suspect as well.
- Anna says that Claudia murdered Dr. Hartmann because she thought he was going to tell Anna and Walter something about Professor Kinsky and Ulla's deaths when he actually wanted to show them the smuggled cigarettes in the cellar. However, Atlantic Connection reveals that Gerhard Wagner, one of the men running this smuggling operation, is a Nazi agent like Claudia, so Claudia may have actually known about it. Before exposing Claudia, Anna finds Dr. Hartmann's unsent letter in which he reports the smuggling operation to the authorities. Claudia could have found this letter as well, so she might have killed Hartmann in order to protect her fellow Nazi agents' secret.
- Giovanni's room is being renovated following Deadly Snowstorm. When the room was first entered, the window was open, and a puddle of melted snow had gathered on the floor. The possible water damage would have given reason for renovation.
- When Anna recounts Flora Molinelli's story and Osvald's childhood at the end of The Heir, she somehow knows details which were never mentioned before, like the name of Osvald's father. Perhaps Osvald has told her the name of his father, but where could she have learned everything else? She discovered earlier that Aldo had sought the services of a private detective, presumably after he had discovered Osvald had a photo of Mario and Flora. Said detective might have already dug into Osvald's background and learned the identities of his parents. Anna gave the detective's business card to Luigi, so after arresting Osvald, Luigi could have phoned the detective who would have told him everything he has discovered after being told that Aldo has been murdered by Osvald who's now under arrest, so by the time everyone's gathered at the dining car, Luigi would have already told Anna what the detective told him.
- Anna says in Unforgiven that her fingerprint kit was lent to her by her friends in the Zürich police. Said friend is probably Dierk, their forensics expert who Anna says has taught her many things that have helped her solve half her cases.
- In The Only Redemption, when we first meet Officer Cozzi's wife, Teodora, we not only see how extremely religious she is, but we also see her accuse her husband of being the father of their housekeeper’s child. Later on, it is revealed that he actually was the father of the housekeeper's child, which led to Cloe's murder. Given how crazy Teodora turns out to be, it's entirely possible that her extreme religiosity might have contributed to her husband having an affair with the housekeeper, as it might take a saint to remain faithful to her.
- When Anna's captive in Forgotten Memento and suffering from amnesia, the player has no access to her journal or the Zürich map whenever the game takes place in her cell. That's because as she notes in the chapter's beginning, her captors went through her belongings.
Fridge Horror
- When Anna decides to check the cellar again in Deadly Snowstorm following Mr. Petersen's death, Claudia volunteers to accompany her. Otto joins them before they can enter. Had he not done so, Claudia might have used her chance to kill Anna while there were no witnesses.
- There's something about the way Anna explains how the murderer of The Only Redemption came to be. Officer Cozzi's deeply religious wife Teodora, embittered that he fathered the child of their housekeeper Cloe Como, kills Cloe in bottled up rage. Since there's a way to avoid arrest, she decides that she has found her calling: making the world a cleaner place by liquidating sinners. She proceeds to murder Regina Valentini for having an affair with Cesare Casale while being in a relationship with Adriano. Anna says that Teodora would have continued her crusade had she not been caught. What Anna describes is a textbook example of the development of a mission-oriented Serial Killer.
- What does the title of the chapter Forgotten Memento refer to? The "forgotten" part seems like it would fit Anna's amnesia in this chapter, but Anna doesn't have a specific "memento" that stands out which she specifically forgets. The "forgotten memento" is possibly Iris Knef herself, whose body is left behind a wall in a cell hidden from the entire world to be forgotten as a memento of the Dada Killer's success.
- The silhouettes of "Oskar's accomplices" in the flashback to Susi's murder in Ladies of the Night resemble that of Gerhard Wagner (now knowing he dons a beret in Forgotten Memento) and Dhara Biguá (whose outfit remains unchanged since Exiled Dead). Anna also finds footprints belonging to a German serviceman and South American yopo snuff at the Knef Gallery when investigating Iris' disappearance, which fits Gerhard's and Dhara's profiles respectively. This all further confirms that Gerhard and Dhara are working for Oskar very closely before the reveal at Anna's kidnapping.
- In No Quarter, Gerhard is revealed to be coercing Ulli to destroy evidence related to Gerhard and his buddies to stop Anna from going after them. This might explain why Ulli failed to tell Anna about Iris' disappearance, to exactly prevent Anna from tracking down Gerhard and his friends.
