Top similar games like Gray Protocol:

Ranko and her friend Astrid must investigate the vanishing of a girl from their school. Learn about the secrets of St. Joachim to find her, but be cautious! A bad step may lead you towards an ugly end...

Staffer Retro is a mystery adventure game where you uncover past incidents related to ‘Mana’, the source of supernatural powers. Gather information through dialogue and exploration, and piece together clues found in documents to guide the choices of Verita Retro, the protagonist.

When the world is coming to an end, who would you want to speak to one last time? Schrödinger’s Call is a visual novel that lets you experience the pain and salvation of human connection, as if you were turning the pages of a picture book.

"Scientific evidence, eyewitness testimony, and objective facts—when these align, the truth emerges. As my grandfather Holmes used to say: Whatever remains, however improbable, must be the truth."

5% of murder cases remain unsolved... it's time to open up these cases and confront the supernatural with forensic science! Solve cases by analyzing evidence and consulting with specialists. Enter a world that artfully blends 2D illustration and real-life visuals!

A visual novel in the romance and adventure genre. Awaken in the Honeycombs, a camp where memory is erased and secrets hum in the night. Forge bonds, defy the Union, and uncover your past. Will you be a pawn or ignite freedom as war looms?

Emma Riley: Dream Detective is a detective game where you must unravel an occult conspiracy spanning the real and dream worlds. Use keen observation to gather clues, carefully interrogate suspects for information, and use your logic and deduction skills to unravel the mystery!

Threefold Recital is set in an oriental fantasy world where the metropolis of Bluescales faces turmoil after a long golden age. The mix of magic, modern, and ancient technologies challenges governance, while tensions between humans, beastlings, and dragons grow. In the shadows, a crisis looms...

Project Judgment is a story-driven detective adventure game where the narrative unfolds as you complete quests. Play as Cain, a detective who has lost his memory. Travel from city to city, solve cases, and uncover the truth behind your forgotten past.

LumineNight is a story-driven detective adventure. Play as Detective Foster and his daughter to solve a series of murders spanning a decade. Interrogate suspects, infiltrate locations, solve puzzles, and gather evidence from crime scenes. Uncover the dark truth behind these killings.

Miles Edgeworth's dramatic turnabouts take center stage! Experience both Ace Attorney Investigations games in one gorgeous collection! Investigate crime scenes and solve tough, intriguing cases through logic and deduction. When Edgeworth's past and present collide, his future begins!

A mystery visual novel taking place aboard the underwater train Marine Express. Follow student Ranko Togawa on her quest to find the culprit on the murder of an accompanying teacher... with lots of surprises along the way!

Ironic point & click adventure where a once brilliant detective quits his trade and lands a job in IT to make a living. But even in the seemingly mundane world of office life, there are secrets to be uncovered. Navigate through puzzles, quirky colleagues, and intrigues to crack corporate mysteries.

Take on the role of Detective Kobayashi, the one and only genius detective who has a reputation for solving any case, however dark or difficult...if he isn't playing games at the office or awkwardly hitting on girls, that is.

Mohism: Battle of Words is a detective game set in the world of wuxia. The game follows Zhang Xiaochen, investigates unsolved cases and comes into his own as a hero. He must rely on his wits and razor-sharp tongue to best his opponents, find the culprit and ensure justice prevails!

The chart-topping itch.io and Newgrounds indie hit comes to Steam, with a slew of enhancements and new features! Step into court as Nina Aquila, rookie defense attorney in this thrilling VN/adventure game hybrid, and fight for justice in a world where all anime genres exist at once!

Become a god and help change the fate of people, even the world! In WILL: A Wonderful World, you will receive letters written by characters living in urban cities. By rearranging the order and combinations of sentences in these letters, you are going to alter the destiny of whomever that wrote them.

In pursuit of coin, hired dagger Arthur finds himself embroiled in conspiracy involving the daughter of a noble House. Who is really pulling the strings behind the scenes?

Embark on a mystical quest that blends Slavic folklore with arcane witchcraft, uncover hidden secrets, and rescue a village lost to the shadows in this magical detective visual novel. Oh, and never forget your cat - he might save you!

Help Tashia unravel the case of a heinous murder and find her cell phone in this point & click, mystery adventure based on Caribbean folklore!

A short literary mystery game set in Oxford and Borneo

Rumor Reporter is a Golden Age whodunit mystery. Play as senior reporter Veronica Chase as you explore Greyhaven Island in the Celtic Sea, 1920s. Choose where to investigate, who to question, and what to publish. Your report shapes public opinion, drives arrests, and changes the island’s future.

This choices-matter visual novel is narrative-heavy, filled with beautifully illustrated characters, intricate stories, and two distinct endings.

It's a mystery game that reveals the truth through an autopsy. Be a forensic doctor and find out why the dead died.

戏班内扑朔迷离的死亡，步步紧逼的幕后黑手，封闭剧场内的死亡倒计时，案件主角的生命和救赎都取决于你的决断。当第一桩案件尘埃落定，你以为可以回到现实世界时，轮回之路才刚刚开始……

This is a Touhou Fangame. Maribel Hearn is a girl with unusual experience with ghosts and supernatural beings. In Cross The Boundaries, you will solve riddles while trying to stay alive, and looking for a way out of the nightmare.