Alternative episode 23 which serves as a prologue onto which "Steins;Gate 0" continues, before it also eventually finished with episode 24 and 25 of this original series.

On a calm day in Akihabara, Okabe and the other laboratory members are invited by Faris go to America. Mayuri and the rest are planning to reunite with Kurisu, who had come back to an American laboratory. A few days later, Okabe's mad scientist persona Hououin Kyouma arrives alone at the airport in Los Angeles, where he may be taking the first step to leading the world into chaos.

Okabe undergoes a personal sacrifice in an attempt to bring the world lines back into order and save the lives of his partners.

Okabe travels back in time with Suzuha to just before Kurisu's death to witness the dawn of the time machine arms race and the spark of World War III.

Kurisu persuades Okabe to let her die and Mayuri live. As Okabe destroys the phone microwave, he gets a critical message from Suzuha.

Okabu hopes to keep Kurisu alive by not hacking with the IBN 5100, but he soon realizes that either she or Mayuri must die in the beta world line.

Okabe locates the missing IBN 5100 and uncovers the identity of the mysterious "FB" but realizes that getting the computer back means losing Kurisu.

When Okabe discovers that Moeka has committed suicide, he attempts to undo the act through D-Mails, leaving Moeka feeling betrayed.

Okabe tries to convince Ruka that she was originally a male and that only by undoing the D-Mails that made the switch can they save Mayuri's life.

When he discovers that Mayuri is still fated to die, Okabe works with Kurisu to reverse the effects of D-Mails that have irreversibly changed time.

Okabe finds Suzuha's father, but his attempt to reunite them results in tragedy that he sets out to correct with the time leap machine.

Suzuha reveals how SERN's plan will lead to a totalitarian government by 2036; Okabe and the rest of the team set out to find Suzuha's father.

While Okabe is devastated by his failure to save Mayuri, Kurisu explains it may not be possible, and Suzuha makes a startling revelation.

Okabe uses the time leap machine to attempt to prevent Mayuri from being killed, but he quickly learns that the mission isn't as simple as he thought.

Kurisu completes her new time machine, which can transmit emotions back in time, and Suzuha fears that she's fated to become a spy for SERN.

When Okabe learns that a TV in the repair shop is linked to the ability to send D-Mail, Kurisu believes it can be used to send emotions through time.

Okabe receives a threatening text message, and Suzuha, unable to find her father, returns home without saying good-bye.

One of the world shifts result in the disappearance of the critical IBN 5100 computer, while another changes the physical properties of the city.

Okabe continues to experiment with D-Mail, resulting in world shifts that only he can remember -- and an attempt to have Ruka reborn as a female.

When Okabe successfully alters time with a D-Mail, the effects lead Titor to believe that Okabe may save the world from its dystopian future.

Okabe experiments with sending texts, now called "D-Mails," into the past and unsuccessfully prevents Moeka from learning the true nature of his work.

Okabe uncovers the gruesome details of SERN's time travel experiments and gets a warning from Suzuha about Kurisu.

John Titor tells Okabe that he can't fully decode the SERN files without an IBN 5100 computer, a rare model that he finds difficult to track down.

Okabe learns that his microwave will send messages to the past, and discovers a shocking secret when he hacks into the SERN network.

Okabe is visited by a self-proclaimed time traveler and conducts the first successful test of his microwave-based time machine -- using a banana.

At a time travel conference, scientist Rintarō Okabe encounters a mysterious woman who claims they met 15 minutes before and is then brutally stabbed.