Originally a laboratory possum, Pith was given "Super Possum"-like abilities from a special formula gone wrong. He defends downtown Possum City, a forest-like city in which its buildings are all giant trees. Taking several similarities from such superheroes as Batman and Superman, a lot of the episodes revolve around Pith Possum saving Possum City from a number of outrageous and ludicrous super villains; The most common one is Dr. Paul Bunion. Pith bore his own secret identity as Copyboy For "A Great Metropolitan Tabloid", Peter Possum, and is always aided by his youthful raccoon sidekick, Obediah.
When not in his hero disguise, Peter Possum is a stereotypical, ultra-nerdy possum who acts and speaks in a sniveling, pitiful manner. He is constantly trying to win the affections of the Tabloid he works for Star journalist, Doris Deer, a beautiful but extremely snobbish human woman who rejects him constantly. In his Super hero guise of Pith Possum, His personality and Speech pattern change drastically. Dressed in a green body suit with a dark blue mask and cape, Pith Speaks in an overly exaggerated heroic pattern. He is brave and fearless, but though at the same time, he is also somewhat egocentric and idiotic. He is always getting himself injured in a cartoonish way, like being run over by his Possummobile.
- Obediah is never seen outside of his costume.
- Despite being in a low level Copyboy job, Pith and Obediah live in a very large luxurious mansion, known as Possum Place.
- Most of their crime fighting gear, including the Possumobile, is provided by Police Commissioner Stress.
- In typical girl reporter fashion, Doris can't stand Peter, but she adores Pith, mostly because of his heroic acts.
- Pith owes much of his crime fighting success and general survival to Obediah.
- He is one of the characters that are not to be called a rat, including Ratigan from The Great Mouse Detective.