Roger Clark, Julia Brown, and Troy Baker provided the motion capture and voices for Jack, Jessica, and Wyatt Taylor, respectively.

[9] The player controls engineer Jack Leary, with two segments featuring his colleague, Jessica Appleton,[10] and traverses the titular Martian station where an emergency alert has been activated.

[11] During exploration, the player finds key cards to open new sections,[12] solves puzzles, and uncovers various logs, expanding the information about the game world.

At the maintenance bay, where Leary attempts to restart the power generators, he is attacked by Wyatt Taylor (Troy Baker), Fort Solis's medical officer.

Through video and audio logs left by the crew, Leary and Appleton uncover the events leading to the Fort Solis lockdown.

When crew members began exhibiting symptoms, Taylor alerted the agency overseeing Fort Solis, but they ignored his warnings and suspended him.

After six months of development, the team secured investment, allowing their studio, Fallen Leaf, to expand to a staff of ten across Liverpool and Warsaw.

This expansion facilitated the outsourcing of certain development aspects to Black Drakkar Games, a Warsaw-based studio that added ten more staff members to the project.

[14] Tinsdale stated that the game's narrative reflected real-world issues, as the pandemic exposed human vulnerability and a hostile environment.

[15] While the developers initially considered incorporating more horror elements, they ultimately opted for a "mystery thriller" to prioritize a character-driven story.

[16] Troy Baker, who portrayed lead officer Wyatt Taylor, said the game was pitched to him as a blend of Dead Space and Duncan Jones' 2009 film Moon.

[17] Tinsdale added that the team aimed to combine the psychological aspects of Jones' film with the "isolated, industrial style" of Dead Space.

For them, an eight-hour TV show is a big commitment [...] We looked at that and thought this game can't go over five hours before the systems get boring.

[13] Although initially conceived as a first-person experience, the game transitioned to a third-person perspective to better facilitate the intended design of continuous gameplay featuring long takes.

The team implemented "key sequences," cinematic story moments with quick time events (QTEs) inspired by God of War (2018) and The Last of Us Part II (2020), which allowed the player to maintain character control.

[19] In December, it was announced that Fallen Leaf partnered with Studios Extraordinaires to develop film and television series based on Fort Solis.

[6] Tauriq Moosa of Polygon compared playing Fort Solis to watching a 4K video on YouTube due to its limited interactivity.

[5] While Emma Kent of Eurogamer and Larryn Bell of Shacknews appreciated the opening parts of the story, they noted that it loses clarity over time and that the ending felt rushed.

"[7] Moosa of Polygon praised the supporting cast for bringing an organic and believable feeling to the dialogues but described the narrative as unconvincing, criticizing its linearity.

[39] Bales of PC Gamer stated that the developers failed to create a sense of suspense, deeming it one of the main shortcomings of Fort Solis, especially since it was promoted as a thriller.

"[37] Jakob Hansen of Gamereactor stated that this mechanic made exploring the environments less interesting,[38] and Aaron Bayne of Push Square considered the combination of slow pacing and dynamic cutscenes "jarring.