When Marshall writes a prediction column for the school paper, he neglects to proofread his work and "Someone will diet" turns into "Someone will die." Things get scary when Marshall's predictions start to come true.
Josie skips Z's science class; the topic is chirality (mirror opposites) - molecules with left handed and right handed forms. During the class experiment a kernel of black hole energy sizzles in the test tubes- suddenly Durst and Professor Z switch roles!
Vaughn discovers a security tape of the Pearadyne explosion showing Sarah leaving behind Victor and speaking to Corrine when she first fell into the wormhole, but refuses to believe that Corrine cannot recall what happened. When they end up stuck together, Josie and Marshall get second thoughts about the two. While the rest of the Science Club tries to find a way to separate them, Vaughn and Corrine sneak into Pearadyne ruins to learn the truth.
When Lucas's gravity sensor is operational, meaning they can now see when the wormhole opens, Josie worries that Vaughn will enter the wormhole without anyone's consent in an effort to talk with his supposedly dead mother. Josie enters the wormhole by herself and is transported to October 4, 1879 (when Blake Holsey High was founded by Avenir), and her friends end up stranded with her when they go through the wormhole to try and bring her back.
Vaughn is lost in the wormhole and travels back in time to April 11, 1977, so Josie goes into the wormhole again to rescue him. Meanwhile, the rest of the Science Club learn more about the nature of the wormhole and the major time periods it connects to in an effort to bring back their friends. When Josie realizes she has been responsible for a number of the events, she breaks a promise to her friends and goes through the wormhole alone to take the floating Qi ball from Victor again.