Ep. 19: Speed and Twinkle confront Cornpone Brotch at his Mount Rushmore hideout.
Speed and Twinkle recover from falling into the river and locate a hidden cave behind the falls. Cornpone Brotch arrives with stolen treasure, prompting Speed to fight his thugs while Brotch flees in the Mach 5. Twinkle uses her escape artist skills to free them from ropes. Trixie, Spritle, and Chim Chim spot Brotch, and Trixie rescues the pair. Brotch retreats to his Mount Rushmore hideout, where the group discovers stolen art and vehicles. Brotch unleashes black panthers, but sleeping gas incapacitates the animals. Speed and his friends are protected by the Mach 5's deflector shield. Spritle and Chim Chim feed the panthers candy, turning them against the thugs. The group escapes to a room where Brotch threatens Twinkle's father, a lion tamer, with a caged lion. Twinkle's father calms the beast, allowing the group to escape. Later, Twinkle performs a trick at Niagara Falls with Speed disguised as the clown.
Episodes
- Ep. 15 · Speed and Kim Race Without Brakes Amidst Rebel Treachery in Flat Hill Country
- Ep. 16 · Speed Racer Invited to Kapetapek's Volcanic Underground Race Amid Political Tensions
- Ep. 17 · Speed races in Kapecapek while Racer X reveals his true identity as Kabala
- Ep. 18 · Speed and Trixie attempt to rescue Twinkle Banks during a dangerous stunt over Niagara Falls.
- Ep. 19 · Speed and Twinkle confront Cornpone Brotch at his Mount Rushmore hideout.
- Ep. 20 · Oriena Flux seeks the GRX engine while Pops confronts her about its dangerous past.
- Ep. 21 · Pops rescues Speed from Oriena's gas-enhanced test drive and helps him overcome his fear of speed.
- Ep. 22 · Dr. Nightcall and daughter steal the Mizmo Beam to build a flying Mach 5 with an atom bomb for Cumulus.
- Ep. 23 · Speed confronts Cumulus at his underwater base, leading to a fatal confrontation involving Dr. Nightcall's daughter.