History is about to be rewritten by two guys who can't spell.
In 1988 San Dimas, California, slackers Bill (Winter) and Ted (Reeves) would rather pursue their band the Wyld Stallyns than schoolwork. Ted's father, the local police chief, threatens to send Ted to military school if they should flunk their history class, ruining their dreams of success. The two struggle to assemble a final report for the class, which is to describe how historical figures would see modern-day San Dimas.
The music of Bill and Ted's band, Wyld Stallyns, has created a utopian future society. Chuck De Nomolos, who detests this society, steals one of the time-traveling phone booths and sends two robots modeled after Bill and Ted back to the late 20th century to prevent Bill and Ted from winning the San Dimas, California Battle of the Bands. Rufus attempts to stop De Nomolos but seemingly becomes lost in the circuits of time.
Bill and Ted are the lead singers of the would-be rock band "Wyld Stallyns." In the future, the music produced by the Wyld Stallyns will unify all the nations of earth, ushering in a new age of peace and groovy prosperity. To ensure Bill and Ted stay on the right path to success, the overseers of the future send an agent, Rufus, to take Bill and Ted through time and meet the most powerful figures in history. Rufus intends to use the time travel technique to help Bill and Ted improve their grades at high school, and in doing so, learn more about the world that, they in the future, will bring peace to (providing of course, they don't bring chaos to the time periods they visit, which they always do). In the eyes of others, this would seem like the ultimate education, but in Bill and Ted's eyes, it's a most excellent adventure!
Two aging rockers turned middle-aged dads, who were once told they'd save the universe during a time-traveling adventure, are inspired to resume trying to crank out a hit song and fulfill their destiny.