Luigi tells Yoshi about the Mario Brothers and Princess Toadstool's first adventure in Dinosaur Land.
Despite King Koopa's objections, Hip and Hop go to Princess Toadstool's school and cause trouble.
During a football game with the cave people, Luigi gets turned into an egg by a Magikoopa. When Bully and Cheatsy take him back to Neon Castle, Mario and Yoshi have to play a football game against the Koopalings to get him back.
King Koopa introduces Dinosaur Land to television and plants a Magikoopa inside each set to hypnotize the viewers.
Luigi teaches the cave people about farming and growing their own food before the coming winter. But when the crops are stolen by Cheatsy, it's up to Mario, Luigi and Yoshi to get them back.
Mario invents the telephone for the cave people. He soon regrets it, however, when he and Luigi have to keep protecting the cave people, who are spending all their time talking on the phone.
After Mario and Luigi yell at him, Yoshi runs away. He then meets the Dino Riders, who are planning to capture the Mario Brothers to get gold coins from King Koopa.
Mario brings Christmas to Dome City to encourage the cave people to act nicer toward each other. When Oogtar tries to get his hands on the best presents, though, he winds up getting taken by the present stealing King Koopa. It's up to Mario to save Christmas for Dome City.
Mario, Luigi and the Princess are captured by a Magikoopa named Wizenheimer. It's up to Yoshi and Oogtar to enter his haunted house to save them.
Mario and company visit King Koopa, Big Mouth and Kootie Pie's circus, where they discover the audience is going to become some hungry dinosaurs' next meal.