Satisfied that the Mach 5 is forever submerged in Lake Icy Chill, the Mammoth Car drivers resume the race. Through his telescanner, Speed sees them leave as he reaches soil. Trixie sends a message in the homing robot to Inspector Detector. The stolen gold is aboard the Mammoth Car. From his plane, Cruncher Block sees the Mach 5 on the road. At the refueling station, Speed and Trixie are fired at. Escaping into a mining tunnel, they jump on top of a speeding trolley car, which crashes.
Meanwhile, at the refueling station, Spritle and Chim Chim sneak out of Cruncher's plane. They, too, escape into the tunnel, which turns out to be Cruncher's headquarters. There, Speed and Trixie are tied to a trolley loaded with three tons of dynamite. Ultimately, Racer X arrives and saves them.
At the next checkpoint, the Inspector searches the Mammoth Car. Again, he finds nothing. Speed reaches the checkpoint; Spritle and Chim Chim slip out to hide in the Mammoth Car.
ブックとの一致 マンモスカーの正体が金塊強奪犯だと剛とミッチーは知ったが、2人は敵のわなにはまってしまう。窮地に追い込まれた2人だったが覆面レーサーに救われた。そして、逃走を図るマンモスカーの追跡が始まる。
