The game's story takes place three years after the events of Crash Bandicoot: The Wrath of Cortex and follows the main protagonist and antagonist of the series, Crash Bandicoot and Doctor Neo Cortex, who must work together to stop the Evil Twins — a pair of interdimensional parrots — from destroying N. Sanity Island.

The game marks the debut of Lex Lang as the voice of Cortex, replacing previous actor Clancy Brown.

Critics mostly praised the gameplay variety, presentation, narrative, humour and Lang's voice performance, but had mixed reactions towards the music and criticised the controls, platforming sections, and camera.

Crash Twinsanity differs from previous entries in the series through its free-roaming gameplay style; the player can explore the game's environments in all directions and travel seamlessly between levels.

[1] As opposed to the "hub room" format utilized by previous games, the player's progression through Twinsanity is influenced by the plot.

Another gameplay style, named "RollerBrawl", involves the player steering Crash and Cortex through the level as they engage in a brawl.

Crash and Cortex attempt to enter the Iceberg Lair through the front entrance, but the door is frozen shut, forcing the pair to take an alternate path inside.

Crash uses Cortex as an impromptu snowboard in an attempt to reach Doctor N. Gin's battleship and gather the Power Crystals, and destroys Dingodile's shack in the process.

After Cortex finds Nina and has an encounter with Madame Amberly, he recalls the origin of the Evil Twins; when Cortex was an 8-year-old student in the Academy, he used his two pet parrots Victor and Moritz as test subjects for a prototype of his Evolvo-Ray, but the experiment resulted in the parrots being transported to the Tenth Dimension, where they would be mutated by the environment's severe "reverso-radioactivity".

Eventually, VU Games gave Traveller's Tales one hour to choose the final title before the default selection of Unlimited.

[18] Lang eventually created a depiction of Cortex that was "master evil with a bit of a childish feminine side that leaks out in his tirades" that had everyone laughing at the lines and the character.

[19] Other cast members include Mel Winkler, Michael Ensign, Susan Silo, Debi Derryberry, Alex Fernandez, Dwight Schultz and Quinton Flynn.

[25] In the United Kingdom, Crash Twinsanity debuted at #25 in the sales charts,[26] and remained within the top 40 best-sellers by the 2004 Christmas season.

[30] In this version, the player controls Crash Bandicoot, who must sprint along a three-dimensional road and dodge obstacles, defeat enemies and collect items en route.

[d] The gameplay aspect of controlling Crash and Cortex in tandem drew comparisons to Jak and Daxter and Whiplash,[35][40][41][43] while the RollerBrawl segment was widely compared to Super Monkey Ball.

[1] Chris Stead of Australian GamePro acknowledged the graphics as "quite pretty", but stated that the collision detection and frequent invisible barriers "leave a lot to be desired".

[38] Brent Soboleski of TeamXbox, Ryan Davis of GameSpot and Nick Valentino of GameZone proclaimed Twinsanity to be the best-looking Crash Bandicoot game to date; they pointed out the increased detail in Crash and Cortex's designs and their smoother and more expressive animations that telegraph their personalities,[40][41][43][47] although Soboleski, Davis and GR Chimp felt the particle and lighting effects and frame rate in the PlayStation 2 version were inferior to those in the Xbox version.

"[40][41] While Valentino enjoyed the game's soundtrack,[43] Bedigian lambasted it as "insanely annoying music that doesn't fit with the wacky and crazy world of Crash Bandicoot".

[44] Vincent Lopez of Official Xbox Magazine remarked that the "mixed-up" score "would find a welcome home in Pee Wee's Playhouse".

[37] GR Chimp described the soundtrack as a "thoroughly weird and catchy" "combination of jungle, pop and a barbershop quartet", and opined that "the quirky approach to the composition helps give the game its attitude".

[39] The humorous dialogue and slapstick comedy were considered a highlight,[g] and the characterization of Cortex and Lex Lang's vocal performance were singled out for praise.

[42] Chris James of Pocket Gamer gave Crash Twinsanity 3D a score of 5 out of 10, noting the game's simple and relatively responsive controls and polished presentation, but criticising the awkward perspective, "very finicky" collision detection, lengthy character animation and long loading screens.

[31] Preceding the European release of Crash Twinsanity, Daniel Tonkin stated that Traveller's Tales was "still very interested in the franchise and I think if the opportunity came up we'd be more than happy to do another game".

[10] A pitch for a new Crash Bandicoot game, tentatively titled Cortex Chaos, was developed by Traveller's Tales after Twinsanity's completion.

Kokopolo was successful enough for him to expand his studio, he would try to approach Activision with a bid to create Cortex Chaos with as many members of the Twinsanity development team as possible.

[13] On August 3, 2017, following the release of the Crash Bandicoot N. Sane Trilogy, Webb sent an open letter to Vicarious Visions congratulating them on the game's success.