A group of friends have customized their microwave so that it can send text messages to the past. As they perform different experiments, an organization named SERN who has been doing their own research on time travel tracks them down and now the characters have to find a way to avoid being captured by them.
One year after the events of the anime, Rintarou begins to feel the repercussions of extensive time travel, and eventually completely fades from reality. Kurisu, being the only companion to remember him, now must find a way to bring him back.
Nicknamed "Sadako" for her spooky appearance, high schooler Sawako begins to break out of her shell when she befriends popular boy Kazehaya.
