On the satellite, Larry has prepared a meal for Otto and Tuddrussel, but he notices that Tuddrussel has been careless about time travel lately. He berates Tuddrussel for stealing so many historical objects since Time Squad is all about "minimal interference," but Tuddrussel ignores him as usual. The History Instability Alarm goes off, and the team sees that the mission involves cavemen before they depart.
Larry tries to use this fairly simple sounding mission as a lesson for Otto, and instructs him on how to handle the situation on his own, emphasizing the need to use a gentle, coaxing method with "minimal interference" on the cavemen. The cavemen are having trouble discovering fire, and Otto tries to explain to them in the way Larry told him to but grows more unsure of how to help as this fails. Impatient, Tuddrussel shoots the cavemens' meat with his laser gun, making an explosive fire. The cavemen are startled, but now have fire in their possession. Larry is not pleased with Tuddrussel's brash way of handling the situation but lets it go since it did get the mission complete in the end. The team is ready to leave when Tuddrussel suddenly swats a fly that lands on him. This horrifies Larry and Otto, who have been trying to keep the interferences to a minimum, and Larry's arm computer suddenly beeps to signal another mission.
The team arrives in medieval England, where the kingdom has been charred. The king greets Time Squad, explaining that all of his knights have been devoured by a gigantic fly monster. The team realizes that this resulted from Tuddrussel killing the fly, which led the species to overcompensate over thousands of years. Tuddrussel is then carried off by the fly monster, but it merely carries him around in circles for several hours. Eventually, Tuddrussel blows it up with one of his antimatter grenades, but when he falls back to the ground, Larry's arm computer beeps again for another mission.
The team arrives on a beach, and, after Larry makes a sighting of the Statue of Liberty and breaks down, they are surrounded by horse-riding fly people. The team is believed to be deserters, so they are arrested and taken to trial, where the judge prematurely declares them guilty and sentences them to be lobotomized and sent to the Poo Mines. Before they are taken, Otto has an idea and tells Larry to take them back to 5 minutes before Tuddrussel swatted the fly.
Back in the stone age, the team watches as the past Tuddrussel shoots the cavemen's fire. Right before he swats the fly, the future Tuddrussel stops him, telling him that his team is from the future. Past Tuddrussel believes they are from "some Bizarro universe" and cautions his team. He gets upset when future Tuddrussel asserts his authority, and the two start fighting. The Larrys and Ottos end up following suit, though not for the same reasons.
Eventually, (much later) the future Tuddrussel wears out the past Tuddrussel, who gives in. All of the fights end, and while future Tuddrussel celebrates, he is approached by a bee. He panics and squishes the bee, setting off the Larrys' arm computers and infuriating everyone else.
Tropes present in this episode include:
- Butterfly of Doom: The fly in the Stone Age.
- For Want of a Nail: The Butterfly Effect is used for a comedic effect as the guys try to fix history after the flies keep mutating out of control through time.
- Kangaroo Court: The trial of the Time Squad is a joke, they are immediately sentenced to be lobotomized and sent to the Poo Mines.
- Mirror Match: The guys fight themselves and all the while mirroring each other's every move, often making it difficult to actually fight.
- Weirdness Magnet: With every moment, the Time Squad have to deal with weird people and monsters in order to get History back to what it's supposed to be.