In Chapter 1, when Dr. Watson is trying to close the front window in the hall, he makes some struggling noises. Before the version v1.0.5905 update (version before July 17, 2026), the game used the incorrect placeholder versions of those sounds, which were performed by the game's writer and director Pascal Cammisotto, and not Dr. Watson's voice actor Daniel Francis-Berenson.

During the intro sequence in developer Draw Me A Pixel's office, the camera pans towards one of the computer monitors which has several application icons and two command lines open. From those, it's possible to find various names, which are parodies of a real-life corporations and/or softwares, including:

• Blotify (Spotify)
• Banger (Blender, as well as the extension ".blend" being changed to ".bang")
• Box (Dropbox)
• Veranda PowerSnail (Windows PowerShell)
• Macrohard Corporation (Microsoft)
• bit (the GitHub command "git")

Additionally, within the command lines is the title of the fictional video game that Draw Me A Pixel are making: "The Amazing Adventures Of Holmes And Watson".

For an interaction during one of the puzzles in Chapter 1, it is shown that Sherlock Holmes is allergic to sheep dander. However, in Chapter 9, when Spoiler:everyone including the main characters turn into Dr. Watson, there's an easily missable interaction with the sheep, where if you throw its dander onto the detective, he won't react at all. The characters acknowledge this with the following dialogue: