The story follows Maxwell "Max" Justice, a teenage street racer, and his efforts to thwart the Monument City Underworld crime ring intent on stealing the Velocity X formula.

[4] Velocity X received mixed reviews across all platforms upon release, with praise for its variety of Hot Wheels cars and game modes, and criticism for its mission structure, vehicle controls, stunt mechanics, and graphical fidelity.

Max learns that the gang responsible for the Engineering Plant and Tire Factory explosions used the commotion as a diversion to steal Dr. Justice's experimental HW Prototype 12 vehicle and a series of disks containing research on a "Velocity X" project.

Dr. Justice tells Max that the Velocity X disks contain a formula for a fuel allowing Hot Wheels cars to travel twice their normal speed, and that his stolen HW Prototype 12 runs on uranium and can turn invisible for short periods of time.

After intercepting the gang's uranium shipment and stopping a hijacked train in Turbine Sands, Max encounters "Backroads" Belcher (Joe Alaskey).

Afterwards, Belcher tells Max that his girlfriend, Nichole "Sparky" Hendrix (Anndi McAfee), was spotted investigating gang territory in Crankshaft Bay.

Sparky contacts Max, telling him about map fragments she found with the names of Dr. Justice and Otto von Diesel (Noah Nelson) written on them.

Dr. Justice asks Max to return to Crankshaft Bay to retrieve a data cube containing backup files for the Velocity X project, but their communications are intercepted by Metacog (Wingert), the gang's robotic assistant.

Otto plans to travel back in time to prevent the production of Hot Wheels cars and erase the Justice family from existence as revenge for his firing.

With the assistance of Gearhead, Max tracks the gang to Monument City's Underworld, where he defeats Nitro, Belcher, Fast Lane, Slick, and Rupert, before battling Otto.

In early 2001, THQ obtained an extended agreement with Mattel to produce video games based on the Hot Wheels intellectual property.

The GameCube's increased processing power also allowed for further enhancements, including an expanded color gamut, improved draw distance, and graphics rendered at 60 frames per second.

[11] The tone of the story was heavily inspired by Speed Racer, focusing on a "good versus bad guy dynamic",[12] and the game's visuals were influenced by the Batman Beyond animated series.

[14] At E3 2002, THQ showcased the GBA, PS2, and GameCube versions of the game across multiple booths, accompanied by Mattel's life-size replica of the Hot Wheels Twin Mill model car.

To promote the game, Mattel distributed a reskin of the Hot Wheels 40 Somethin' model car exclusive to Toys "R" Us—featuring decals of the THQ and Velocity X logos—bundled with the CD-ROM.

[23] In 2002, Mattel distributed a Velocity X PC demo disc with a limited edition run of Hot Wheels Racing Ferrari F2002 1:24 scale models.