Act One - When Cats are Maddened by the Midnight Dance

“Cats are much like you and me”. They have their own family home but venture out at night to meet with the rest of their tribe. Once the humans have left, the cats reveal themselves on stage. They explain to the audience the world of the Jellicle tribe . The cats then explain that cats have three different names.The name used by the family, a more dignified name and a secret name. Tonight is a special night for the Jellicle tribe. For tonight is the night of the Jellicle Ball, where one cat will be chosen to journey to the Heaviside Layer to be reborn into a new Jellicle life.

The Invitation to the ball is danced by Victoria, a young white cat. Munkustrap introduces the Old Gumbie cat, Jennyanydots. She "sits and sits and sits" all day, while at night she rules over the mice and cockroaches, teaching them various activities. Next, The Rum Tum Tugger makes an extravagant entrance. The Rum Tum Tugger is a tom who the female cats adore. He loves being the centre of attention and always does as he pleases.

An old cat stumbles towards the tribe. It is Grizabella. She was “The Glamour Cat” but left the tribe many years ago to explore the outside world. The cats resent her trying to come back so she leaves. The dapper Bustopher Jones is an elite cat, very well connected and belongs to many prestigious clubs. All the cats are honoured by his presence.

At the end of Bustopher Jones' song, we hear a crash made by the evil cat Macavity, and the cats run off the stage in fright. Mischievious giggling signals the entrance of Mungojerrie and Rumpleteazer. They are petty burglars, and enjoy playing pranks and causing trouble for human families.

Finally, the Jellicle Patriarch, Old Deuteronomy arrives. He is a large old cat respected and admired by all the tribe. All the cats rejoice, as he is the one who will soon decide which Jellicle cat will go to the Heaviside Layer.

The tribe entertains him with a show introduced by Munkustrap. The cats perform The Awful Battle of the Pekes and the Pollicles. It is a story about two dog tribes clashing in the street and subsequently being scared away by the Great Rumpus Cat. Another second loud crash is heard sending the cats scurrying. Old Deuteronomy entices the tribe back and the grand Jellicle Ball begins. Grizabella reappears once more, determined to be a part of the celebrations. Once again, she is shunned by the other cats, but sings to them of her Memory.

Act Two - Why Will the Summer Day Delay — When Will Time Flow Away?

Old Deuteronomy sings of ‘happiness’. Gus, the Theatre cat,  (short for Asparagus) is introduced. He is an old cat that once was a famous actor. He is accompanied by Jellylorum, who tells of his wonderful life. Gus then remembers how he once played the ruthless Growltiger, The Terror of the Thames . He tells the story about the pirate's romance with Griddlebone and how he was overtaken by the Siamese and forced to walk the plank.

We are then introduced to Skimbleshanks, The Railway Cat, who is unofficially in charge of the railway train. He is a perfectionist and all must be right before the train can start.

With a third crash and a devilish laugh, Macavity’ The Mystery Cat appears. He is a “master criminal” who never is found at the scene of the crime. The villainous Macavity captures Old Deuteronomy and disappears. The cats set out to find him.  Demeter and Bombalurina sing what they know about Macavity, as they both have had some sort of past with him. Macavity returns disguised as Old Deuteronomy. When revealed by Demeter, he fights with Munkustrap and the other male cats.

The Rum Tum Tugger suggests that the cats ask for the assistance of the magical Mr Mistoffelees. He can perform many magical tricks that no other cat can do. Mr Mistoffelees succeeds in bringing back Old Deuteronomy. He is praised by all the cats. Old Deuteronomy can now make his Jellicle choice.

Grizabella appears for the final time. Old Deuteronomy allows her to have a chance to address the cats. She appears weak and lonely. Her appeal touches the hearts of the cats and with Old Deuteronomy’s encouragement they welcome her back to the tribe. He then decides that she is to be chosen as the Jellicle cat to be reborn. She is guided to her ‘stairway to heaven' and all the cats rejoice. Old Deuteronomy gives his closing speech to the human audience telling them how to ad-dress a cat.