Takuya doesn't know his father is alive until the device proves it. The show doesn't waste time convincing you that parallel worlds matter, because the first rule of time travel fiction is simple: if your dad vanished into another dimension, you're going after him, logic be damned. Every choice branches into a new world, and every world has a version of the people he loves wearing a different face. The pacing stumbles in the middle stretch, stretching mystery past the point where it grips. But the core emotional engine never quits: a kid with a device that lets him rewrite reality, trying to find one version of his father where things didn't break. That desperation is what keeps you watching.
Takuya Arima's father vanishes without a trace, leaving behind only a cryptic package and a letter describing impossible things: parallel worlds, alternate dimensions, the fabric of reality itself fractured into infinite branches. Inside the package sits a device that shouldn't exist, one that lets Takuya slip between worlds like turning pages in a book. At first he thinks it's a prank, but each jump reveals a new version of Earth, new versions of people he knows, new versions of himself. Every world holds clues about his father's disappearance, yet every answer raises darker questions. Why did his father send this to him now? What was he searching for across these dimensions? And more unsettling still, what happens when Takuya realizes that jumping between worlds carries a price, that some versions of reality are collapsing, and that something ancient might be waiting for him at the edges of existence. Takuya races through infinite possibilities trying to piece together the truth before reality itself unravels completely.