Revealing mistake: At the end, when all the historical figures are going back into the phone booth, you can see the trap door in the back open and the people go through it. It would be kind of tight to fit all of them in the booth at the same time.
Bill & Ted's Excellent Adventure (1989)
1 revealing mistake
Directed by: Stephen Herek
Starring: Keanu Reeves, George Carlin, Alex Winter
Other mistake: Beethoven didn't seem fussed nor resentful of Napoleon being part of the group. Historically he temporarily admired him and wrote the Third Symphony inspired by Napoleon's ideals of Europe's new hope of enlightenment but later despised him after he crowned himself Emperor of France in 1804 and furiously scribbled out his name off the title page of his Third Symphony and named it Eroica which he originally titled it as "Bonaparte Symphony" due to his former admiration of Napoleon.
Trivia: The shots of the French army are from the 1956 film War and Peace.
Question: Why was Beethoven arrested? He wasn't doing anything illegal.
Answer: While it's not unusual for musicians to try out new instruments (playing a few rifts and even entire compositions) in a music shop, Beethoven's extended sampling-keyboard performance went wild, drawing an enthusiastic mall crowd into the relatively small music shop. The shop manager no doubt felt overwhelmed and called in mall security to clear out the shop before any damage and/or theft occurred. Keep in mind that the security team was already scrambling to respond to several simultaneous disturbances throughout the mall, all caused by 7 strangely-dressed oddballs (more than half of whom only spoke obsolete dialects and ancient languages). The time-travelers were, thus, probably all perceived as one group of pranksters or escapees from a mental institution.
Charles Austin Miller