CATS the musical is a theatrical play by Lord Andrew Lloyd Webber centered around a number of interesting cat characters.
Webber's musical production, aptly named CATS, is based on a collection of nursery rhymes. Written by T.S. Eliot, they were originally published in 1939 as Old Possum's Book of Practical Cats.
Since these were verses from nursery rhymes without any central theme to hold it together, the collection wasn't really ripe for a musical theater production. The characters were certainly colorful, though, and you can guess that by their names alone.
These "practical cats" included such characters as:
For nursery rhymes, that seems like a mouthful to me!
The thing that pulled it all together for Lord Webber was an unpublished handwritten verse given to him by Eliot's widow. This verse, called "Grizabella, the Glamour Cat," offered Webber the basis for the central character needed to create the play.