Bill (Winter) and Ted (Reeves) have spent so much time forming their rock band, The Wyld Stallyns, that they're flunking history. Whoa, duuuude! And when Ted's dad threatens to send him away to military school, Bill and Ted realize it could mean the most heinous end of The Stallyns! Luckily, a guardian angel from the future, Rufus (Carlin), has come to them with a most bodacious solution: a time-traversing phone booth to take them into the past to learn about the world from some of history's most influential personalities. Their journey through time turns out to be a blast but will they learn enough to pass their class?