Note: "Kyoukaimenjou no Missing Link" specifically refers to the 25th OVA episode of the original series (often titled "Egoistic Poriomania" in Japanese) or serves as a bridge to the narrative of the Movie. This paper treats the "Missing Link" concept as a critical narrative gap-filler between the series and the subsequent narratives, focusing on the themes of memory and existence.
This episode recontextualizes the entire series. We realize that the "Happy Ending" of the original show wasn't a miracle—it was a debt paid in blood and decades of suffering by the Okabe we see here. This version of Okabe has to live through World War III, lose his mind, and spend fifteen years building a time machine just to send a video message to his past self. He is the "Missing Link"—the bridge between total despair and the Steins Gate worldline. Steins-Gate- Kyoukaimenjou no Missing Link - Di...
He typed back: “Who is this?”