Maria
The “Juliet” in this interpretation of Shakespeare’s romantic tragedy is Maria. Maria is the younger sister of Bernardo, the leader of the Sharks, and she has only recently moved to New York as an immigrant. She is pure-hearted, beautiful, but spirited, determined to live an exciting life and explore the possibilities of living in a new place. She is a fierce romantic, and even after Tony has killed her brother, she remains loyal to her one true love, sure that love is the most important thing in life.
Tony
Tony used to be the leader of the gang known as the Jets, but he’s put that life behind him and found a job. He is less tough than his fellow gang members, and wants to make something of himself, not simply become a victim of the neighborhood in which he lives. Like Maria, he is a pure-hearted romantic, and before he's even met his one true love he has an intuition that his life is about to change. Tony is a peaceful person at heart, but he still kills Bernardo is a vengeful fury during the rumble.
Riff
Tony’s best friend, Riff, is the leader of the Jets. He is far more headstrong and impulsive than Tony and can be quite hot-headed and rambunctious. His song "Gee, Officer Krupke" outlines the ways that he feels like the adults in his life have let him down. Gang life has provided Riff with a structure and a family he never had.
Bernardo
Bernardo is the leader of the Sharks, a determined and serious young man who suffers under the indignity of being treated like a second-class citizen in main-land America. He resents the racism of the neighborhood and is fiercely protective of his younger sister, Maria, especially when he finds out that she is in love with an American boy.
Anita
Anita is Maria's best friend and Bernardo's girlfriend. She is slightly older and more experienced than Maria, and she tries to give Maria advice even though she knows deep down that Maria must follow her heart. Anita has a good sense of humor, a fiery personality, and a wry attitude in many situations, but she also wants to do what's right. Like Bernardo, she ends up believing that the Americans are not to be trusted, especially after the Jets molest her at Doc's.
Officer Krupke
So omnipresent a force is Officer Krupke that the Jets sing a song especially about him. The lyrics mock the policeman’s inability to make their lives any better. Krupke is somewhat dimwitted and has no idea what the young people he is meant to be "protecting" are going through.
Ice
Ice takes over for Riff as the leader of the Jets after Riff is killed. True to his nickname, his most influential piece of advice for his fellow gang members is to keep it "cool."
Anybodys
Anybodys is a short-haired young woman in the neighborhood who would rather be a member of the Jets than wear a dress. The Jets continually reject her, but she insists that she is one of them, eventually earning Ice's recognition when she provides some important information about Chino's intention to kill Tony.