Craig Marshall is a 15 year old sophomore who was disowned by his group of friends in his freshman year after getting in a fight with two of them. Now, perpetually lonely, Craig signs up for a club called TIME TRAVELLER'S HELPER, ran by Amy Blance and Leanna Walsh, two young ladies who are sophomore as well. While Craig only joined the club in an effort to gain friends, he finds out that the club is in fact about communicating with your future self through text. While Craig first scoffs at this, Amy explains a situation where her future self sent her a text and was life changing.
After hearing this, Craig decides to give the exercise given a go and communicates with his future self. After a less than desired outcome, the next day his future self texts him notifying him that he has been selected for a new mission. He has to find and stop a girl who is planning on committing suicide. Her suicide will alter the world line that he is in forever. He has until winter break to do so.