The Detective (also called The Watcher by The Witch) is the protagonist of The Room VR: A Dark Matter. They are employed by the 'E' division of the Bloomsbury, London Police. They are investigating the disappearance of Dr. Rupert Montgomery when they come into contact with The Craftsman and are sucked into his plans through promises of aid for their investigation. With help from The Witch, they are able to thwart The Craftsman's plans and seemingly trap him in the Null, freeing all of his victims' souls in the process.
- The Room VR: A Dark Matter
Since The Detective is represented by the player, they have no appearance besides a pair of tweed gloves as hands. It is intended for the player to project themselves onto The Detective, so they also have no official gender.
The Detective is very observant and cunning, able to follow in the footsteps of several of The Craftsman's victims and defeat him with a little help. They are quiet and don't react very often to the many strange things that happen throughout the course of the game, but do provide snippets of commentary in the game's tutorial and upon entering a new area. They express relief upon returning to the police station, but very little else as far as emotion goes. They are very duty-driven and determined to solve the case assigned to them.
After being employed at the Bloomsbury Police Station for some time, The Detective was assigned to the case of Dr. Rupert Montgomery's mysterious disappearance. They investigated the storage room at the British Institute of Archaeology in person to compile information before returning to the station. Hoping to find a report from Sarge, they instead found a note from him about a parcel that had been dropped off for them and left in a safe by a "peculiar old gentleman." After the lock corrupts and The Detective is forced to crack the safe, they discover the first of four "curious" artefacts. This instantly teleports them to a strange dimension where they find the first direct note from The Craftsman, as well as the eyepiece. They solve another puzzle and are brought inside the Null.
They receive a note from The Craftsman asking them to learn the stories of three people who disappeared, the first being Dr. Montgomery. The Detective is able to teleport to the British Institute of Archaeology's storage room and begin investigating The Archaeologist's disappearance. After solving a number of puzzles and seeing visions of Montgomery, they discover a second artefact housing The Archaeologist's soul. They are brought back to the Null to deliver this artefact before being teleported to The Chapel of the Sacred Guard. They repeat a similar process for The Reverend, drop off the third artefact at the Null, and are teleported to The Witch's Cottage.
As they solve the various puzzles in the cottage, The Witch contacts them directly through her notes and warns them of The Craftsman's treachery. After collecting her soul, returning to the Null and subsequently being abandoned by The Craftsman, she frees herself and guides The Detective to an excavation camp that The Craftsman hijacked. They descend into a temple of the Null and, using the various tools there, trap The Craftsman's soul in an artefact. They are teleported to the Null for the final time and place the artefact on a platform, causing all of the souls collected by The Craftsman to be freed. The Witch uses the power of the Null to open a doorway back to the police station. The Detective expresses relief at returning to their own world, before receiving a final letter from The Witch warning them to be cautious and vigilant.
Because The Detective is a blank slate intended for the player, very little is known about the character except that they are sharp-witted and can solve the many puzzles thrown at them with relative ease. They are even able to trap The Craftsman with minimum guidance.
Sarge is presumably short for Sergeant, and a colleague of equal rank to The Detective. Since he signed his letter to The Detective informally, it is implied that they are close enough to be on somewhat unprofessional terms.
Dr. Rupert Montgomery
The Detective is determined to discover the cause of The Archaeologist's disappearance through any means necessary, but it is unclear if this is because of loyalty to his occupation or loyalty to protecting the people of London.
The Detective blindly trusts The Craftsman at first, going along with his requests in hopes of gathering more information about their case. When The Witch enlists The Detective for help in capturing The Craftsman, they do not resist and willingly capture his soul. It is unknown if The Detective felt any strong way about The Craftsman after learning that he would betray them.
The Detective goes along with The Witch's plan to defeat The Craftsman without question. They do not express gratitude towards The Witch for her help in guiding them or returning them to the police station, nor do they react to her words of praise and warning in her final letter.