With only a few days before their high-school graduation, Bill S. Preston, esquire and Ted 'Theodore' Logan are doomed to flunk out of school. The history teacher, Mr. Ryan, decides to give Bill and Ted a chance. If they can ace an oral exam on the topic of how a famous historical personality might react to modern times, they will be allowed to pass. If not, Ted's father will place Ted in military school, thereby disbanding the Wyld Stallyns, the heavy metal band that was formed by Bill and Ted. Bill and Ted get help from an unexpected source: Rufus, an Emissary from the Future. It seems that in Rufus' time, Bill and Ted's music is the basis of all existence, and if the Wild Stallyns are disbanded, Rufus's world will no longer exist. Bill and Ted are whisked off in a time machine to retrieve a few historical characters for their oral exam so they can pass, but Bill and Ted soon discover that finding the historical characters and getting them to the high school won't be easy.