Collin the Speedy Boy and Looney Tunes: When Worlds Unite, also known as Collin and Bugs: Speed and Laughter United, is a made-for-TV animated film produced by Warner Bros. Animation for WB Kids, being a crossover between The Chronicles of Collin the Speedy Boy and the Looney Tunes/Merrie Melodies franchise.
After a portal sucks the Looney Tunes characters into FingerTown, they meet the hero of FingerTown, Collin the Speedy Boy, but when Bryte teams up with/hires Pinky and the Brain to destroy Collin, the Looney Tunes, Collin, and his gang must stop them.
Collin the Speedy Boy
- Jason Griffith as Collin the Speedy Boy, Austin and Cooper Elledge
- Scott Menville as Tommy the Opossum
- Dee Bradley Baker provides the sound effects for Tommy.
- Grey DeLisle as Heather Lansdell; Kaitlyn Wood and Jasmine Todd
- Phil LaMarr as WesDragon and The Elefish King
- Kathryn Cressida as Stacie the Speedy Girl
- Colleen Villard as Baylee Mardis
- Ashley Johnson as Riley Logston
- Jeff Bergman as Bugs Bunny, Daffy Duck, Tweety Bird, Sylvester Pussycat, Sylvester Junior and Henery Hawk
- Bob Bergen as Porky Pig, Speedy Gonzales, Hubie, Bertie and Marvin the Martian
- Jeff Bennett as Foghorn Leghorn
- Billy West as Elmer Fudd
- Maurice LaMarche as Yosemite Sam, Wile E. Coyote, Pepé Le Pew and the Barnyard Dawg
- Frank Welker as the Road Runner, Hector the Bulldog and K-9
- Dee Bradley Baker as Squeaks the Squirrel
- Rob Paulsen as Mac Gopher
- Jess Harnell as Tosh Gopher
- Jim Cummings as Taz, Beaky Buzzard and Gossamer
- Kath Soucie as Lola Bunny
- Grey DeLisle as Tina Duck and Petunia Pig
- Tress MacNeille as Penelope Pussycat, Miss Prissy, Granny and Witch Hazel
Tiny Toon Adventures
- Charlie Adler as Buster Bunny
- Tress MacNeille as Babs Bunny and Marcia the Martian
- Jeff Bergman as Plucky Duck
- Gail Matthius as Shirley the Loon
- Billy West as Hamton Pig
- Frank Welker as Gogo Dodo, Furrball Pussycat, Calamity Coyote and Little Beeper
- Candi Milo as Sweetie Bird
- Kath Soucie as Fifi La Fume and Li'l Sneezer
- Maurice LaMarche as Dizzy Devil
- Rob Paulsen as Arnold the Pitbull, Fowlmouth and Concord Condor
- Cree Summer as Elmyra Duff
- Danny Cooksey as Montana Max
- Rob Paulsen as Yakko Warner and Dr. Scratchansniff
- Jess Harnell as Wakko Warner
- Tress MacNeille as Dot Warner and Hello Nurse
- Frank Welker as Thaddeus Plotz, Ralph the Guard, Buttons and Runt
- Maurice LaMarche as Squit
- Jeff Bennett as Bobby
- Dee Bradley Baker as Pesto
- Sherri Stoner as Slappy Squirrel
- Kath Soucie as Skippy Squirrel
- Nancy Cartwright as Mindy
- Bernadette Peters as Rita
- Julie Brown as Minerva Mink
- Grey DeLisle as Teary Eyed Bryte
- Billy West as Eli
- Eric Bauza as Fang Suckle
- Jeff Bennett as Nasty Canasta and the Crusher
- Jim Cummings as Rocky
- Frank Welker as Mugsy
- Rob Paulsen as Pinky
- Maurice LaMarche as the Brain
- Jess Harnell as Walter Wolf
- Acme Acres
- Warner Bros. Studio Lot
- Bugs: "Welcome to FingerTown! Population: Many Fingers?" Is this the place where creatures called Fingers lived?
- Buster: Well, I heard stories that it was once Louisana, but people had to evacuate 'cause of the dangerous Teary Eyeds.
- Buster: Well, probably no cute girl lives here in- *sees Riley Logston, and falls in love with her* FingerTown...
- Cooper: Izzy, are you sure that we want that Tasmanian devil in our HQ?
- Izzy: Pft! He appears very friendly.
- Taz: *barks (meaning: That's because I am!)*
- With some exceptions, the majority of the cast reprise their roles from their respective shows.
- Elmer Fudd, Yosemite Sam and Marvin the Martian are allies to the main characters in the film rather than villains.
- The movie shares the same animation as The Chronicles of Collin the Speedy Boy, the hit series aired on WB Kids.
- This project started off as an anime crossover series, but as it was revamped into a television movie, CTSB received a anime series, The New Adventures of Collin the Speedy Boy.
- The Looney Tunes universe is modeled after The Looney Tunes Show universe, albeit with some differences:
- The characters retain their The Looney Tunes Show Season 2 designs, but with their classic personalities, with Taz remaining as Bugs' pet.
- Daffy Duck's personality is more closer to his Robert McKimson's incarnation rather than the Chuck Jones' one.
- Mac and Tosh are siblings.
- Sylvester Junior, Hector the Bulldog, Hubie and Bertie and Nasty Canasta, who were absent from the show, appear in the film (Squeaks is an exception, since Wabbit came after the ending of the show).
- The neighborhood is part of Acme Acres (the setting of Tiny Toon Adventures) rather than Los Angeles.
- While Daffy Duck and Speedy Gonzales remain living in the same house, Bugs Bunny lives with Squeaks and Taz in his traditional rabbit hole.
- Elmer Fudd remains as a hunter.
- Gossamer is Witch Hazel's creation rather than her son.