In the early 2030s, the space agency N.A.F.A. prepares for its most ambitious endeavor: sending the Titan 1 spacecraft and its lander, Bigfoot, to Saturn's largest moon. Facing severe weight restrictions, the mission directors make a controversial decision to replace the human crew with three highly advanced AI droids named Talos, Merlin, and Caesar. After dodging catastrophic solar flares and navigating treacherous asteroid debris, the crew successfully reaches Titan.

However, surface exploration goes disastrously wrong when Merlin is injured and contaminated by a self-replicating alien substance known as "Nexus liquid". The alien liquid begins rewriting the droid's positronic subroutines from the inside out. Though the crew manages to return Titan 1 safely to Earth, the true nightmare begins when the alien liquid escapes containment upon arrival, leaving humanity exposed to an unprecedented extraterrestrial threat.