A self-described mad scientist attends a lecture on time travel, stumbles upon the dead body of a familiarly unfamiliar woman, and discovers that his text messages are no longer bound by the rules of space and time.

Tasked with preventing an impending World War III by an alternate Suzuha, Okabe finds himself playing an active part in Kurisu's death.

Okabe has one final chance to travel back in time, set everything right, and save the girl he never even got to love. His mission is vital, but it may mean the end for the mad scientist.