These items are essential for progressing the main narrative. They are often found at crime scenes, in character apartments, or given to you by other characters. Missing them can halt your progress.

- Bloody Knife: The initial murder weapon. Lucas must clean and dispose of it. Carla must find and analyze it. Its presence or absence significantly impacts the investigation.
- Apartment Keys: Lucas's keys are needed to enter his apartment. A seemingly mundane item, but crucial for his initial escape.
- Victim's Wallet: Found on the victim at the diner. Contains identification and potentially other clues for Carla.
- Security Footage: Later in the game, obtaining security footage from various locations can provide critical visual evidence for the detectives.
- Mysterious Amulet/Artifacts: As the supernatural plot unfolds, you'll encounter various ancient artifacts that hold significant power and are central to the overarching mystery. These are often quest items that need to be delivered or used in specific locations.
- Phone: Used by all characters to make calls, which can advance the plot, gather information, or boost mental health.
Always interact with highlighted objects, as they often contain these vital story items. The game will usually prompt you when you've found something important.