The origins of Mr. Peabody and the WABAC machine: Mr. Peabody finds Sherman in the street being beaten up by some bigger boys. At first, he doesn't think that he's the right sort of boy- but when he sees how he is treated in the orphanage, Peabody decides to adopt him. At first, there's a problem when they won't let a dog adopt a boy- but he goes to court, and the judge decides that if a boy can have a dog, then a dog can have a boy! Sherman comes to live with Mr. Peabody, who builds him the Wayback Machine in order to keep him busy. They go back in time to Rome, and then to see Ben Franklin.

Sherman and Peabody meet Napoleon Bonaparte and his suspenders.

Peabody and Sherman go back to the court of King Arthur and help him sort out Black Tuesday. Every Tuesday, something goes wrong: plagues, invasions and even termites!

In 1807, Robert Fulton's steamship is pitted against Robert E. Leech's sail-powered boat.

Mr. Peabody and Sherman use their Wayback Machine to go back in time to Buffalo Bill and His Wild West Show with Annie Oakley. A wonderful comedic twist puts Oakley on her way to sharpshooting fame!

Peabody and Sherman go back to 1903 and visit the Wright Brothers at Kitty Hawk.