Kevin Michael Richardson, the voice of Chairman Drek in the first game, was originally brought in to reprise the role in the movie. However during production, he was quietly replaced by Paul Giamatti, but the movie company accidentally mailed Paul's paycheck to Kevin's address.
Initially, Sony was planning to make a live action adaption of the video game "Ratchet & Clank" in 2005. Edgar Wright turned it down to do Hot Fuzz (2007), Guillermo Del Toro was brought on, but walked over disagreements regarding the tone of the movie. Other directors including Jon Favreau, James Gunn, Brett Ratner, Joss Whedon and Michael Bay were also considered before the project was scrapped entirely due to budget constraints.
The voices for Ratchet and Clank are the same actors who voice the characters in all the games, except for the original game, which is the only entry in the series where Ratchet was voiced by another actor.
The second movie based on a video game to have a completely new game based on its movie plot released on game consoles. Street Fighter also released a game that was based on the movie likeness of its characters.
In the PlayStation 4 version of Ratchet and Clank, the voice of Victor von Ion is done by Mark Silverman, but in the movie he is voiced by Sylvester Stallone.
At one point, one of the Galactic Rangers' robots falls off a platform, and lets out a noticeable "Wilhelm Scream" (a famous sound effect used in many Hollywood films). Another robot shouts out to his fallen comrade "Wilhelm!!"
When one of Chairman Drek's minions is thrown off the side of a bridge, as he screams on the way down, another cries out his name as "Wilhelm". The "Wilhelm Scream" is the most famous reused scream in all of cinema
While Clank scans a species database in an attempt to identify Ratchet's species (a Lombax,) Daxter from Jak & Daxter, and Sly Cooper, from Sly Cooper and the Thievius Raccoonus, appear on the scan.
When Clank is identifying Ratchet's species type, Sly Cooper, Daxter (from Jak and Daxter) and Dan Johnson, a former late employee of Insomniac Games (producer of the video games).