(Some spoilers below.)In the original Bill & Ted's Excellent Adventure (1989), Bill (Alex Winter) and Ted (Keanu Reeves) are high school students in danger of flunking history. If that happens, Ted's father will ship him off to a military academy, thus breaking up their band, Wyld Stallyns. But the band is destined to usher in a future utopia, which is now threatened. With the help of a time machine in the form of a phone booth—provided by Rufus (played by the late George Carlin), a messenger from the year 2688—the pair travels through history, meeting Socrates, Billy the Kid, Sigmund Freud, Beethoven, Genghis Khan, Joan of Arc, and Abraham Lincoln, among others.
In the sequel, Bill & Ted's Bogus Journey (1991), the boys must defeat their evil robot doubles from the future to preserve the utopian society based on their ideals. Among the highlights: Bill and Ted must play a game (Battleship, Clue, and Twister) against Death (William Sadler) in order to escape from hell and return to Earth to win the Battle of the Bands. The Grim Reaper turns out to be a hell of a bass player, joining Wyld Stallyns until a falling-out over his fondness for 40-minute bass solos.Bill and Ted Face the Music revisits the BFFs as middle-aged men, still living in San Dimas, California. They have teenaged daughters—Wilhelmina/Billie "Little Bill" Logan (Brigette Lundy-Paine) and Theodora/Thea "Little Ted" Preston (Samara Weaving)—and frustrated wives, Princess Joanna (Jayma Mays) and Princess Elizabeth (Erinn Hayes), who insist on couples counseling. Per the official premise:
The stakes are higher than ever for the time-traveling exploits of William "Bill" S. Preston Esq. and Theodore "Ted" Logan. Yet to fulfill their rock and roll destiny, the now middle-aged best friends set out on a new adventure when a visitor from the future warns them that only their song can save life as we know it. Along the way, they will be helped by their daughters, a new batch of historical figures, and a few music legends to seek the song that will set their world right and bring harmony in the universe.
"You still have Bill and Ted, but they’re now middle-aged. They’re not teenagers, but you retain the essential qualities of them—this good-hearted ludicrous optimism," said Parisot. "They’ve been best friends for years. They think alike, they act alike, they never doubt their friendship for a second. If those qualities came through, then you would have a Bill and Ted movie."Writers Ed Solomon and Chris Matheson, who created the characters all those years ago, had long wanted to revisit Bill and Ted. They came up with the plot and basic structure for Face the Music, but then faced the daunting task of trying to write characters they hadn't inhabited for decades. Matheson admitted he wasn't sure it would work. "Are they going to make sense to us?" he recalls wondering. In the end, "I wouldn't say it was effortless, but it was like riding a bike," he told Ars. "They somehow still live on, and they do make sense to us."
One thing that helped during the writing, according to Solomon, was not rewatching the first two movies in preparation. "I'm glad in retrospect that we didn't, because we would have been trying to copy them too much," he told Ars. "We just said, where would these characters be now? Let's just feel them that way and write from that place. So the movie has its own sensibility, and I'm proud of that."