I’ve always had a fascination with AI’s throughout mainstream media. SkyNet, Lt. Data, GLaDOS, even Roy Batty (What? He DOES count) – there’s just something about the different perceptions on created intelligence and how humanity responds to them. It’s part of the reason I was so intrigued by the latest title from Bithell Games, Subsurface Circular. Effectively a visual novel (or “text-based adventure” for those outside of that niche) it follows the story of a robotic detective who resides within the titular underground transit system, investigating the disappearance of a fellow Tek.

However, the main reason my interest was piqued – outside the fact that the previous two games with Mike Bithell’s involvement were pretty good – was its self-confessed short run time. Labelled as “a Bithell Short,” the intention was to deliver a high-quality narrative that can be played through in a single session, with a reduced price point to match. So, for half the price of a cinema ticket, I dived in to see if the aim matched the reality.

Although Subsurface Circular is a linear tale, the conversation system at the heart of the gameplay creates an illusion of something much grander than it actually is. It’s all thanks to the branching nature of responses, in which players can speak to various passengers on the train to discover new clues. Finding new leads unlocks new topics, allowing the player to go back and forth between different Teks to crack the case.

This sort of gameplay isn’t anything new, but it is aided by an engrossing narrative and excellent world building through Bithell’s writing. The goal may be to find clues to solve the case, but the response choices that range from straight forward, witty, and sarcastic allows the player to learn more about the relationship between humans and Teks. It also lets players build up their own persona for the robotic protagonist, which adds a personal touch to the player’s actions even though it doesn’t alter the course of the story.

This includes being able to make a few musical theatre references, something I wholeheartedly approved of.

While Subsurface Circular does throw a couple of puzzles into the mix, it’s clear that delivering its narrative is the main priority. There is even an option to turn on assistance to ensure players can push on instead of sitting there stumped. As someone whose puzzle-solving skills flick between ‘moments of genius’ and ‘utterly useless’ I didn’t think there was anything too taxing, but it’s great that the option is there should it prove too problematic or time-consuming.

The simple and clean UI makes navigating the gameplay a straightforward affair, ensuring that new elements are adequately highlighted. If there is one complaint, it’s that I was unaware there was a map of the transit line until near the very end which, considering some of the minor questions relate to it, was pretty annoying. What wasn’t annoying, though, was the art design. From the variation in mech designs, to the small details found throughout the carriage, to the perfect tone of Dan le Sac’s soundtrack – everything falls into place within Subsurface Circular. While it’s not quite a minimalistic approach, there’s a simplicity to the design that works with the short run time.

And short it is, as I managed to finish my playthrough in just over two hours. In that time, I dived into the noir-esque mystery, sassed a couple of robots, and found myself pondering the relationship between man and machine. In a way, I feel it does for adventure games what Thomas Was Alone did for platform games – takes a relatively simple gameplay mechanic and fleshes it out with an engaging narrative.

That said, while I did enjoy my time with Subsurface Circular, I can’t say with certainty that I will hold it in the same regard as its rectangle-based processor in the years to come. Maybe it’s the length, or maybe it’s the “tell, not show” nature of its world, but I definitely came away thinking that there should have been so much more. Perhaps that was the point – end the experience before it outstays its welcome – but I don’t think its hooks will remain in me for the long run.

There’s also the lack of longevity, as you can see everything the game has to offer in under three hours. Of course, that’s ultimately not the point of Subsurface Circular, as I feel Bithell Games have achieved their aim of creating a short and well-formed narrative title. Whether this opens the door for other smaller, more focused indie titles remains to be seen (especially without Mike Bithell’s influence to help it find success) but it’s a trend I’m all for if done correctly.


  • Well written sci-fi narrative.
  • Great use of branching conversation to unravel the mystery.
  • Clean UI that highlights important aspects as needed…


  • … except for the transit map button (tip: hit the icon in the middle of the train indicator to view it!)
  • Its small form might leave some players yearning for more.
  • If you’re looking for something with longevity, look elsewhere.

The Short Version:DO-Review-Score-08

Bithell Games’ experiment into short-form gaming might not rank as the studio’s best release, but if you’re after an evening’s worth of sci-fi entertainment, Subsurface Circular delivers an enjoyable & well-written adventure title.

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Platform: PC

Developer: Bithell Games

Publisher: Bithell Games