The film tells the story of Willy McBean, a young schoolboy who teams up with an anthropomorphic monkey named Pablo to prevent the villainous professor Rasputin Von Rotten from changing the history of the world, using the newly created and duplicated "magic" time machine.
Written, produced and directed by Arthur Rankin, Jr., with Jules Bass and Larry Roemer as associate producers, the film uses a team of voice actors under the soundtrack recording supervision of Bernard Cowan in Canada, including Larry D. Mann as Von Rotten, Billie Mae Richards as Willy And Paul Soles as Pablo the Monkey. Tadahito Mochinaga supervises the "Animagic" stop motion process at MOM Productions in Japan, the same team behind the animation for The New Adventures of Pinocchio (1960–61) and Rudolph the Red-Nosed Reindeer (1964).
Plot
Willy McBean is sick of trying to learn history for school. Meanwhile, an evil scientist called Rasputin Von Rotten is building a magical time machine so he can go back in time and be the most famous person in history. A Spanish-English talking monkey named Pablo climbs through Willy's window. He explains that he escaped from Von Rotten and he tells Willy what he is planning to do. Pablo stole the plans to the time machine.
Willy builds his own machine to go back in time to stop Von Rotten. The machine isn't working properly. They end up with General George Armstrong Custer, and escape moments before Custer is killed in the Battle of the Little Bighorn (1876).
They then arrive in the Wild West, where they meet Buffalo Bill Cody and his Indian pal, Sitting Bull. Von Rotten plans to become the fastest gun in the west. Von Rotten asks Bill for a showdown, but both guns are sabotaged before anyone can be shot.
Von Rotten moves onto his next target, Christopher Columbus. Once there, disguised as a Chinese trader, he convinces Columbus's crew that they should mutiny. Once more McBean and Pablo stop the evil professor by showing the crew that land is not far off.
After that, Von Rotten goes back to England in the days of King Arthur in the kingdom of Camelot, but Pablo and Willy get Arthur to pull Excalibur the magic sword that can talk. A talking green dragon then crashes into Camelot in an effort to eat everyone, but King Arthur and Excalibur are able to drive him away.
As they return to the present, Von Rotten shows the students history through his magic machine (in the form of a movie projector) during history class.
