Elliot Greaves, a 25-year-old janitor, stumbles upon an alien time machine hidden in the school basement. Intrigued and hesitant, he activates the device and embarks on a journey to 1969, witnessing the first moon landing. However, he quickly realizes that each time jump creates an alternate timeline, leaving him to grapple with unintended changes. Obsessed with the machine, Elliot explores historical events, only to learn that even small actions have profound consequences. When an alien creator warns him of temporal instability, Elliot must revisit and repair his altered timelines, ultimately choosing to sacrifice the machine to restore order and protect reality.