"Mars: Horse with No Name" is a manga series that blends elements of science fiction, adventure, and psychological drama. The story is set in a dystopian future where humanity has colonized Mars, transforming it into a harsh, unforgiving environment. The narrative centers on a young man named Rei, a skilled but emotionally detached pilot who operates a unique biomechanical horse-like vehicle known as a "Mars Runner." These vehicles are essential for survival on the planet, serving as both transportation and protection against the hostile Martian terrain and its dangers.

Rei's life takes a dramatic turn when he encounters a mysterious girl named Aria, who claims to have no memory of her past. Aria possesses an uncanny connection to the Mars Runners, suggesting she may hold the key to understanding their origins and purpose. As Rei and Aria form an uneasy alliance, they are pursued by various factions, including corporate entities and rogue militias, all seeking to exploit Aria's abilities for their own gain. The duo embarks on a perilous journey across Mars, uncovering secrets about the planet's colonization, the true nature of the Mars Runners, and the dark history of human experimentation that ties them all together.

The plot delves into themes of identity, memory, and the ethical implications of technological advancement. Rei's stoic demeanor contrasts with Aria's vulnerability, creating a dynamic relationship that evolves as they face escalating threats. Supporting characters, such as Rei's former comrades and enigmatic figures from Aria's past, add layers of intrigue and moral ambiguity to the story. The series balances intense action sequences with introspective moments, exploring the psychological toll of living in a world where survival often comes at the cost of one's humanity. Through its intricate world-building and character-driven narrative, "Mars: Horse with No Name" presents a compelling exploration of resilience and the search for meaning in a fractured society.