Episode 8
Chaos Theory Homeostasis, Pt. 1
Steins Gate - 08 - Large 30
Japanese Name: 夢幻のホメオスタシス
Romaji Translation: Mugen no Homeosutashisu
Release Date: May 25, 2011
Production Staff
Screenplay: Toshizo Nemoto
Storyboard: Kanji Wakabayashi
Director: Kanji Wakabayashi
Theme Music
Opening Song: Hacking to the Gate
Ending Song: Toki Tsukasadoru Juuni no Meiyaku
Episode Navigation
Previous: Episode 07: Divergence Singularity
Next: Episode 09: Chaos Theory Homeostasis II
Episode Glossary

Chaos Theory Homeostasis I  (夢幻のホメオスタシス, Mugen no Homeosutashisu) is the eighth episode of the anime adaptation of the visual novel Steins;Gate .

The latest experiment for Okabe and his lab mates leads to the disappearance of one of their own. Next, they'll attempt to use their time travel technology to make a young boy's dream a reality.


August 3rd, 2010; about 4:25 PM

Still in the lab, Okabe has just received a text message from John Titor, asking him to be the savior of the world. Okabe is shocked by this at first, but then breaks out into laughter. He declares that, as a mad scientist, all he longs for is chaos and destruction.

Daru walks into the lab. Okabe announces that they will continue their Phone Microwave experiments, despite the threat of Mr. Braun’s anger. Kurisu retorts that she is against doing the experiments. Okabe comments that she was all for the experiments this past afternoon. When Daru asks when this happened, Kurisu realizes that Okabe has already changed the past using a D-mail.

Kurisu asks why Okabe has been able to retain his memories. Okabe notes that he, according to John Titor, possibly has the ability to keep his memories as he crosses world lines. Okabe dubbed the ability “Reading Steiner.”

We then briefly see Ruka at the Yanabayashi Shrine, mulling over the lottery ticket that Okabe told him to buy.

Back at the lab, Okabe, Kurisu, and Daru are trying to jump world lines by sending a D-mail to the past. They send a D-mail five days in the past to Daru, telling him the position of the cards in his match with Faris so that he could win. The D-mail seems unsuccessful, but to be sure, they have Daru call Mayuri to ask her what the outcome of the match was. She confirms that he was beaten “in the blink of an eye.”

Okabe and Kurisu go to the local park to discuss the matter at hand further. Okabe suggests that Kurisu should send the next D-mail, but she refuses. She says changing the past feels unfair: she doesn’t desire to change anything that’s made her who she is today. Okabe turns the tables on her, saying that, like a mad scientist, she’d rather watch others take risks while she sits back and watches.

Their conversation is interrupted when Okabe receives a text message from Moeka, asking if she can send a D-mail. Okabe ignores the message and tries to continue talking, but he receives another text. And another. Finally, Moeka suddenly appears in front of them, surprising them. She verbally asks if she can send a D-mail.

August 4th, 2010

The next day, Okabe is sitting on a bench outside the CRT shop, presumably waiting for the other lab members to show up. Mr Braun and Nae arrive at the shop. Mr Braun berates Okabe, suggesting that he’s lazy and keeps scaring his little girl. Mayuri arrives shortly after, giving Nae and Okabe a piece of candy.

Then, Suzuha shows up on her bike. She asks Okabe if he got to talk with John Titor. He confirms that he did, but says that he’s not sure if he should believe what he says. This surprises Suzuha for some reason.

Kurisu then shows up. As soon as she makes her presence known, Suzuha glares at her (for the third time). This confuses everyone. Moeka suddenly appears, taking pictures of everyone.

Now in the lab, Okabe, Kurisu, Daru, Mayuri, and Moeka are about to conduct another experiment. Okabe instructs Moeka to come up with a simple D-mail message that would make it easy to tell if the past was changed. Moeka (via text message) says that she wants to tell her past self (four days ago) not to buy her current cellphone.

Just when they are about to start up the Phone Microwave, Ruka shows up at the lab with a watermelon. He says it’s a present for messing up the lottery ticket Okabe told him to buy. Then, Ruka promptly leaves.

The rest of the group continues where they left off. The Phone Microwave is started up, after which Moeka quickly sends the D-mail. Okabe’s “Reading Steiner” activates.


Okabe, realizing that his “ability” kicked in, stands in front of the Phone Microwave as before, where Daru and Kurisu are talking, though he cannot hear what they are saying. He then realizes that Moeka is missing from the lab, as well as the watermelon that Ruka brought not too long ago. He inquires of them both: Mayuri says that Ruka never came by and no one but Okabe remembers who Moeka is. Kurisu discerns from Okabe’s actions that they sent another D-mail.

Okabe, fearing that the D-mail wiped Moeka from existence, checks his text message history. Moeka’s messages are still there. He then sends her a text. Rather quickly, she replies, saying that she is busy.

Later in the day, we see Okabe and Kurisu on the roof, talking about the last D-mail and its effects. Kurisu asks Okabe if his “Reading Steiner” ability is real, after which Mayuri arrives. Mayuri and Kurisu leave together, leaving Okabe alone. Thinking to himself, he confirms that his ability is real, which makes him wonder if he truly is the “savior” that John Titor speaks of.

Kurisu and Mayuri are walking together, talking about a possible “no-boys” sleepover that they should have. Mayuri then gets a call from Ruka, which excites her for some reason.

August 5th, 2010; 2:01 PM

Back at the lab, Ruka has come to visit Okabe, Daru, and Mayuri. After some chitchat about Ruka forgetting his sword, Mayuri coaxes him into trying on one of her cosplay outfits, much to Ruka’s embarrassment.

After a few awkward moments pass, along with Kurisu’s arrival, Ruka makes known that he’s come to the lab to ask for a favor. He tells everyone that he wants to send a message to the past.

He explains that the day before, he had come by with a present to make up for messing up the lottery ticket. It was then that he overheard the lab members talking about the last D-mail they sent to the past and its effects it had.

Mayuri asks Ruka what message he would like to send; Ruka answers, saying that he wants to be a girl.

This confuses Kurisu, who still thinks Ruka is a girl. Okabe tells her to find out for herself, which she does. She is left dumbfounded.

Okabe is skeptical about how a text message can change someone’s gender. Ruka voices the idea that mothers who eat lots of meat when they’re pregnant have a boy, and if they eat lots of vegetables, they have a girl.

Okabe says that he will grant Ruka’s request, which makes her and Mayuri happy. Daru questions Okabe’s decision, but Okabe reassures him that nothing will happen, to which Kurisu agrees. Okabe then dubs Ruka as Lab Member No. 006.

Okabe, realizing something, asks Ruka when he was born. He questions as to whether Ruka’s mother had a cellphone while she was pregnant. After discovering that his mother probably didn’t have a cellphone then, he theorizes that they can send a message to a pager instead. After finding that his mother most likely had a pager at that time, Okabe tasks Ruka with finding out if his mother had a pager and, if so, getting its number.

August 6th, 2010; 11:54 AM

Ruka finds out that his mother had a pager and also found its number. She also concocted a message to send, which had to be shortened due to character limits. They then start up the Phone Microwave. Ruka sends the D-mail, and “Reading Steiner” activates.


Okabe is, again, standing in front of the Phone Microwave. Behind him are Kurisu, Daru, Mayuri, and Ruka, doing normal activities. Okabe, staring at Ruka, wonders if the D-mail they just sent really worked.

Kurisu catches him starting at Ruka and calls him out, causing Ruka to feel embarrassed. Okabe then assumes that Ruka is the same as before. However, since “Reading Steiner” activated, he knows that something has changed. The question is, “What?”