Private Toad is a Nicktoon about an incredibly clueless toad detective named Leroy and his rooster partner, Russel. It is a spoof of mystery movies like Sherlock Holmes and Dick Tracy. It is based off a Fort House Cartoons short. Each episode ends with Leroy and Russel giving a short public service announcement called a Mystery Moral.
- Leroy The Toad, the main character of the series who is a toad. He is gullible, clumsy, and not very intelligent. His bumbling nature gets him and Russel into danger, but he always gets out of trouble through his trusty gadgets or pure luck. He is determined to solve any mystery he can find. He also has a British accent. He is a parody of Sherlock Holmes.
- Russel, the deuteragonist of the show. He is Larry's cowardly, hapless, timid partner. He often suffers from Leroy's antics. He is a parody of Dr. Watson.
- Mr. Roo, Leroy and Russel's short-tempered boss who is a kangaroo. He often assigns them to their cases.
- Bul E, the main villain of the series who is a bull gangster. He is a gunslinging mob leader who will do anything to become the king of mafia. However, his plans are always foiled by Leroy and Russel. He has an intense phobia of hamsters.
- Dr. I.C, a mad scientist penguin. He is obsessed with snow and wants to freeze the world in ice.
- Milker, a milk spewing mutant cow monster. He wants to make everyone in the world drink milk.
- Swamphead, a crocodile who wanted to be a wrestler, but couldn't because animals called him a weak, ugly, pathetic cold blooded monster. He has always been ridiculed and pushed around, even at a young age. His dream is not only to let cold-blooded creatures roam the Earth, but also make those who wronged him suffer. He is incredibly strong and it doesn't take much to get him angry.
- Itcher, an ant who uses plants for his own criminal needs.
- Duckler, a duck assassin. He is 100% serious and has no signs of being goofy. He isn't really a villain, but more of an anti-hero.
- Wampeater, an anteater who can suck things up like a vacuum.
- Deathsnake, a venomous snake who can poison anything with his teeth.
- Featherhead, a hawk who uses his wings to slice things.
- Chompa, a beaver who can chomp up anything.
- Admiral Wolf, A gray wolf who wants to turn the seas into nothing but dust.
- Lord Moose, a villain introduced in the final season. He is the ruler of the 30th century and will stop at nothing to contain power of the universe.