Overture

The overture to Cats is one of Andrew Lloyd Webber's best known orchestral numbers. It kickstarts the show and is accompanied by a segment known as "Green Eyes".

Green Eyes
The staging for the overture starts in darkness with the lights occasionally flashing to punctuate the music. As the music builds, anonymous Cats emerge into the dark with flashing green eyes on their heads. As quickly as they appear, they disappear, leaving the audience wondering just what happened. Many productions have a central circular lighting rig, a "chandelier", that rises from the stage floor with cycling white lights, during the final section of the overture.

In the original London production, the final moments of the overture saw the stage revolve into place, a jigsaw suddenly making sense as sight lines are resolved, and the chandelier rises from centre stage into place.

Music
The overture is based solely on the Jellicle theme in its various forms - this theme goes on to recur throughout the rest of the musical. The orchestra opens with an "agitated, chromatic fragment" of the theme that grows into a dissonant fugue. This leads into the four-phrase version of the theme, which in turn leads into its grand eight-phrase melody complete with rousing fanfares and percussion. The eight phrase goes back on itself a few times, building in momentum each time until the big finish.