It's been 20 years after elementary school, the students of Ms. Frizzle's class at Walkerville Elementary have grown up since the 1990s and have new lives. After hearing the news that Ms. Frizzle has presumably died, the reunite at her funeral. As they are collecting her belongings, they notice her time travel earrings are glowing. They figure out that Ms. Frizzle is alive and is stuck some where back in time. The gang reunites to travel back in time to find what time period Ms. Frizzle is and save her. Meanwhile, General Auskott, the military officer in charge of Area 51, has been investigating Ms. Frizzle's activities for years and now has the opportunity to finally capture her by planting a spy posing as her long lost son to join the gang's rescue mission.