On the first day of high school, Haruhi Suzumiya make an announcement that stunned everyone: "I don't have any interest in ordinary people. If anyone here is an alien, time traveler, slider, or esper, please, come see me! That is all."

Kyon, a totally normal human who happens to have the misfortune of sitting at the desk in front of Haruhi's, wondered at first if she was joking. But Haruhi Suzumiya is always serious. Always. In any case, Kyon certainly never intended to get involved in her antics. But when a casual conversation accidentally gives Haruhi the idea to form a club dedicated to the discovery and investigation mysterious phenomena, Kyon finds himself already in over is head, especially when Haruhi makes him her first recruit. Other members of the club include Nagato Yuki, a quiet, bookish girl; Mikuru Asahina, an all-too adorable girl chosen by Haruhi to be the club's "mascot"; and Koizumi Itsuki, an always-smiling boy chosen by Haruhi to play the role of "mysterious transfer student". And so the SOS Brigade is born!

Things only become weirder and more difficult for Kyon, however, when he finds out the Haruhi has unknowingly surrounded herself with the very people she has been wishing all this time to discover: Nagato Yuki's actually an alien, Asahina Mikuru's a time traveler, and Koizumi Itsuki's an esper! And why have all of these people appeared in the first place? Why, for Haruhi, of course! Three years ago, Haruhi caused some sort of disturbance that each one of them finds worth investigating. And Kyon, for whatever reason, seems to be the only "normal" one in the whole group. His biggest question: why him?