(I have included many spoilers. Skip this if you don't want to know what happens. And this is ONLY the musical version of the plot; Maguire's novel is entirely different.)

Like many interesting stories, this one begins at its ending. A familiar scene of everyone rejoicing over the evil witch's death opens this play. Glinda arrives and helps the crowd sing their song, which leads into a discussion of the past. "Are people born wicked? Or do they have wickedness thrust upon them?" We see a nice little flashback involving the "secrets" of the witch's family . . . her mom cheated on her dad. "Have another drink of green elixir," says the ratty man, and they proceed to have their little affair when Daddy is out of town. Then their baby is born with green skin and immediately spurned--it freaks the family right the heck out. Spurred by someone in the crowd accusing Glinda of having been the witch's friend, she begins to tell a story of how she met her . . . at school.

Now, both of them go to Shiz University, where it is possible to learn magic if the headmistress, Madame Morrible, decides to take you. Galinda arrives already being admired by other students, while Elphaba arrives being chided by her father to take care of her sister, whom she is pushing ahead in the wheelchair. Other students are kind of gaping at her, unsure of what to think of the weird green girl, so she just launches into "Okay, let's get this over with--NO I'm not seasick, YES I've always been green . . ." and points out that her sister is a perfectly normal color. Her ranting is cut short by her father telling her to stop making a spectacle of herself.

Galinda informs Madame Morrible that she came to Shiz just to study sorcery with her, but Morrible is on a high horse and says she doesn't take a student every semester. While Galinda is regrouping trying to figure out how to change this, Morrible announces that she has decided to take Nessarose into her own quarters to provide the best care. After all, her father is the ruler of Munchkinland. So Elphaba needs a roommate now that she isn't going to be with her sister--and Morrible asks someone to volunteer to take her in just as Galinda is trying to get her attention to protest the earlier outrage. Of course, her hand signal is taken to mean she will take Elphaba in.

Things start moving too fast for poor Elphaba to comprehend when Morrible insists everyone go to their rooms, and she panics at the sight of her sister getting wheeled away. She yells "LET HER GO!" and funny lights start blinking, and suddenly the wheelchair rolls away and back toward Elphaba. She apologizes for acting out, but Madame Morrible is so impressed with this strange green girl's magic abilities that she decides, hey, I'm going to concentrate all my teaching on YOU so that maybe one day you can be the Wizard's right hand woman!

Understandably, this pisses Galinda off--she wanted to get into the sorcery program and now this freaky green chick is preventing her from achieving her dreams. Immediate loathing develops, of course, and on top of this now they have to room with each other.

After being told that her "weird quirk" is a fantastic talent, Elphaba is understandably awed and excited, and sings us a little song about her ambition. In a revealing peek at her aspirations, she wonders aloud if the Wizard might help her get rid of her green-ness--you know, not because SHE wants it or anything, just because he might think "shouldn't the girl who's so good inside have a matching exterior?" At the end of her song she's envisioning herself as "half of Oz's greatest team"--the Wizard and herself. (It's kind of the "I wish I had a daddy who loves me" song, she's projecting parental identity onto the Wizard, which isn't entirely inappropriate.)

But there is the present to deal with. She now faces a roommate who not only hates her, but encourages the entire student body to hate her. While writing home to their families, both girls voice roommate complaints--Galinda says her roommate is "unusually and exceedingly peculiar and altogether quite impossible to describe." Elphaba just gives up and describes her roommate in one word: "BLONDE." We get to hear them sing an amusing song about how much they hate each other, with the crowd chiming in with sympathy for Galinda somewhere in the middle. Well.

Being that Elphaba is again a social outcast, she develops an unusual closeness with her teachers, particularly Dr. Dillamond. The doctor is a Goat--see, in Oz, there is a big difference between animals and Animals. The Animals can talk and are treated as citizens, while plain old animals are dumb beasts like anywhere else. After becoming upset at a hateful message about Animals written on his board, Dillamond tells Elphaba that some bad things are afoot in Oz--he's heard some "dreadful things" about other Animals who hold positions of respect getting their positions taken away from them, which has an effect on their ability to speak. Elphaba assures him that someone needs to tell the Wizard about this--"That's why we HAVE a Wizard!" They just decide to keep their fingers crossed that Dr. Dillamond isn't next on someone's sinister list.

Now comes the complex part. There is a big dance at the Ozdust ballroom, and the prince Fiyero makes his entrance. In a song, he declares his philosophy: "Nothing matters but knowing nothing matters." In other words, it's best to just dance through life having fun, and of course Galinda thinks this carefree life is a great idea; they're perfect for each other. Immediately they become romantically involved, and he wants to take her to the dance. Oh . . . but wait, there's little Boq. Galinda has an unfortunate admirer who manages to find the courage to tell her that he hopes she'll save a dance for him. Galinda manages to get rid of him by suggesting he invite someone else, pawning the munchkin off on Elphaba's sister Nessarose. (She figures Nessa won't say no--who's going to invite the girl in the wheelchair?) In making it sound like she just wishes the best for the poor crippled girl, she tricks Boq into inviting Nessa to the ball, just to get him out of her hair so she can concentrate on Fiyero. She also decides (with the help of some friends) to give a really ugly hat to Elphaba so that people will laugh at her at the dance. She assures her that it's very fashionable--"You know black is this year's pink!"--and convinces her roommate to wear the big pointed witch hat. Hahaha.

Anyway, Nessarose and Elphaba have a little chat about Galinda's behavior--apparently Nessa feels VERY indebted to the popular princess for finding her a date, and she wishes there was something she could do to repay her. Elphaba takes this to heart and goes to Madame Morrible on Galinda's behalf, getting her to accept her into the sorcery program. Oh yeah!

When Galinda finds out that she's been accepted through Elphaba's doing, she feels REALLY bad for making people laugh at her with that hat, and kind of takes their attention away from her by dancing with her in support. They become tentative friends, and Galinda presses that they exchange their secrets. In confidence, they tell each other some private things: Galinda says she's going to marry Fiyero (even though HE doesn't know that), and Elphaba says that everyone in her family hates her and her sister's condition is her fault. (Nessa's father made her mother consume what he thought was a remedy against making her come out green too, and it caused her to be born crippled.)

Galinda feels REALLY bad for her roomie, and decides that she is going to devote herself to making Elphaba popular. (Of course, Elphaba doesn't really want that, but Galinda doesn't know any other way to make someone happy except by giving them what she thinks they need.) She sings a very entertaining song about the importance of popularity while giving Elphie (as she calls her) a makeover. Elphaba doesn't completely appreciate that, but Galinda is undaunted.

Next we start to see some disturbing stuff. Elphaba's Goat professor is taken away, no longer permitted to teach. A new professor comes in with a caged Lion cub and proclaims that the cages help assure that the Animals will never learn to speak. As a prime Animal activist, Elphaba flexes her muscles (well, her magic), halfway unintentionally casting a spell to make everyone "do something." They are incapacitated, and only she and Fiyero are unaffected. Fiyero happens to have been very intrigued by Elphaba's passion and drive, and he assists her in freeing the Lion cub. Even though he's kind of empty-headed, he is attracted to the strength of her character, and begins to have a bit of a crush on her. It's also mutual . . . but Elphaba decides to try to put it out of her mind, because she knows her friend Galinda really likes Fiyero, she can't do that to her. Besides, she tells herself--"I'm not that girl"; he's already chosen someone golden-haired and winsome. Sigh!

Still shaking off the dust from that, Elphaba receives the joyous news that she's been invited to the Emerald City to demonstrate her power for the Wizard! Everything's a bit awkward because relationships are falling apart. Fiyero's confused about his relationship with Galinda, and starts talking about his and Elphaba's heroic acts together. Galinda wants to be cool too, and says she's going to change her name to Glinda because that's what Dr. Dillamond always mistakenly called her; it'll be a display of her devotion to him. Elphaba feels bad for her friend and tells her to come along for the ride to the Emerald City. She's overjoyed.

Everything is not so great with Nessarose either; Boq doesn't really like her, but she's clingy, having never had the romantic attention of anyone else because of her condition. And now she's finally realizing that Boq likes someone else. She's not too happy.

We get to see a big celebration when Glinda and Elphaba get to the Emerald City--they see how wonderful it is, and declare that they both want to live there someday even though today it's just visiting. After all, "it's all grand," says Glinda, "and it's all green!" (Guess who said that second part.) "I think we've found the place where we belong!"

The audience with the Wizard seems to go smoothly . . . everyone is introduced, and he wins Elphaba's trust by giving her a sugar-coated explanation of his views of the Ozians and his fatherly role. He hopes, he says, to help Elphaba with her ascent, because "everyone deserves a chance to fly." But then he suggests that she prove her magic ability by transforming his assistant monkey into a winged monkey. If she can do this with a really old and powerful book called the Grimmery, he will have proof of the strength of her magic. Her spell actually ends up working too well; the spell did more than she expected, and gave a whole hidden cage of monkeys wings as well. When the Wizard explains that they will now be his army of spies, Elphaba gets PISSED. The Wizard is behind all the Animal rights suppression! It's all because he wants to lead the people of Oz against some common enemy no matter who it is. (He'll be more adored by the population that way apparently.) And beyond that, the Wizard is no wizard--he has no magic at all. That's why he wants Elphaba . . . he wants to use her. And she doesn't appreciate that. She steals his Grimmery and escapes.

Of course, now she has made a huge enemy of the Wizard of Oz! Glinda really doesn't like this, and meets with her to plead that she reconsider before going off to serve her destiny (fighting the Wizard's evil ways). She begs her friend to apologize to the Wizard and just do what she had always dreamed of, but Elphaba's illusions are shattered, and she will not just lie down and be a tool of the man. Glinda cannot bring herself to ditch her reputation and come with Elphaba even though she makes a convincing case . . . what else do you expect from someone whose driving force all her life has been peer pressure? Anyway, they are very sad to part and now be on opposite "sides," but they both wish each other happiness. Elphaba invites Glinda, "So if you care to find me, look to the western sky." And off she flies, to end Act I.

Some time has gone by when the second act opens, and now Fiyero, Madame Morrible, Nessarose, and Glinda have official government positions. Glinda has the official title "Glinda the Good," Morrible is the right hand woman of the Wizard (press secretary), Nessa is governor of Munchkinland, and Fiyero seems to have been put in charge of the Wizard-sponsored push to find Elphaba. (She's now been declared a menace and is thought dangerous, a criminal.) We see a happy song of Glinda announcing her engagement to Fiyero . . . which isn't exactly something he's agreed to! He's surprised by his engagement party, but he goes along with it, telling Glinda that if it will make her happy of course he will marry her. (She says she hopes it makes him happy too, but he says, "You know me. I'm always happy." Hmm.) Fiyero gets really pissed off when he hears that all these people are making up dumb rumors about Elphaba ("I've heard her soul is so unclean, pure water could melt her!"). He leaves in a huff, and Glinda covers it up by saying he's just going off to get her a drink. Morrible makes an announcement (as "press secretary") saying that "the witch" is jealous of Glinda for her recognition by the Wizard, making up a different "official story."

Things are not good in Munchkinland either, because Nessarose's sanity is slipping away. She loves Boq and has done everything she can to keep him with her, including taking away the rights of munchkins so he CAN'T leave her. She's very bitter, though, and when Elphaba actually shows up to hide out under the cover of her sister (hopefully), Nessa gets all mad and basically tells her if SHE'S so powerful how come she never used magic to try and cure her inability to walk? Well, feeling taunted, Elphaba does cast a spell, and is able to put a charm on Nessa's slippers to help her walk. For a moment everyone's very happy; Nessa's like "YAY I CAN WALK!" and Elphie's like "YAY I DID SOMETHING GOOD WITH MY MAGIC FOR ONCE" and Boq's like "YAY NOW NESSA DOESN'T NEED ME TO WAIT ON HER HAND AND FOOT ANYMORE AND I CAN LEAVE!" Oh no. Well that's not what Nessa wanted. So she gets very angry, snatches the Grimmery, and casts a spell on Boq to take his heart away. (Ya know, since it didn't belong to her, it should belong to no one!) Elphaba intervenes with her own magic, and turns Boq into a metal person so that having no heart won't kill him. So he's still alive, but not human anymore. When he awakes, Nessa twists the truth and blames his condition on her sister, making Boq swear a deadly oath against her.

Attempting to further her cause, Elphaba flies to the Emerald City and tries to break the flying monkeys out of their prison--Animal rights and all that, you know. But the Wizard interrupts her. And he uses his considerable charisma to try and tempt her into working with him after all, making the Ozians stop pursuing her by rehabilitating herself as his friend rather than his enemy. And this approach almost works too, until she finds out that the Wizard has taken away the powers of speech of her old professor, Dr. Dillamond. (I guess that's better than in the novel version where Dillamond is assassinated, but either way it sucks.) All her anger comes back and she rejects the Wizard's proposition, and almost doesn't get away except that Fiyero helps defend her, showing up at the right time. Glinda also sees her there, and is excited to meet with her friend again . . . but then she has to join the witch-haters' club because FIYERO IS RUNNING OFF WITH HER! Um, well I guess the engagement's off.

In private, Elphaba and Fiyero spend the night together and have their intimate moments. Despite the fact that this relationship throws both of their lives into complete turmoil, Elphaba can hardly believe her good fortune--she got the guy! But her getting the guy causes Glinda to have a moment of jealousy, and she gets with Morrible and the Wizard to spring a trap for Elphaba. She suggests starting a rumor that her sister is in trouble, which will bring Elphaba running. But Morrible decides rumors aren't enough, and uses her considerable weather sorcery powers to arrange for the famous "A house dropped on my sister!"

Of course, Elphaba takes the bait and is horrified to find that her sister has been crushed by a flying house, and she has no one to blame for it but the little girl who happened to be inside.

Glinda and Elphaba have a shouting match (and a little more than that), and it is through that action that Fiyero reveals his true colors, saving Elphaba and making everyone aware that he is on her side. The Wizard's flunkies capture Fiyero and string him up on a stick to let him die in a field, for assisting the enemy. Elphaba retires to the castle Fiyero gave her directions to, and tries to cast a spell to save him from death. She's so disoriented and enraged and panicked that she doesn't even know what to do, and feels she's failed her love. She comes to the realization that every good thing she ever did got interpreted as wicked, and decides maybe she should just be wicked forever. The mobs mobilize to take her out.

Meanwhile, Glinda starts to figure out that the whole murder of Elphaba's sister and all that junk was orchestrated, and Glinda gets in trouble with Morrible for trying to take a stand against it. Seeing Morrible's true colors when she's told to just shut up and do what she's told, she goes off to find her friend.

Convinced she needs to be "wicked," Elphaba has captured Dorothy and really wants to take out her rage at her sister's death out on the poor girl, but Glinda convinces her to let Dorothy go. She receives a note from her monkey regarding Fiyero: We find out later that he is all right, having been transformed by her magic so that being tortured and strung up did not hurt him. (Wow, now he really is brainless--he's the straw man, the scarecrow!)

Poor Elphaba just can't take it, and says the world was too much for her. Glinda, on the other hand, seems to have mastered it, she thinks; she tells her best friend that she wants her to forgive her and do what's right. See, Glinda's got the admiration of the population, she must have done something right--and Elphaba makes her promise not to allow the masses to find out they're friends, because it will weaken her popularity, which she now needs to use to rise up against Morrible and the Wizard. They make their agreement, and Elphie gives Glinda the Grimmery to help her with her quest. They agree that they are friends, changed "for good" by friendship. And they say goodbye.

The famous scene of the wicked witch melting actually happens, but it turns out it's a ruse. Elphaba is alive, hiding in a trapdoor . . . and her lover the scarecrow comes to get her, at which point they escape to a world outside of Oz where they can be happy.

A really nice scene follows of Glinda coming into her own. First she gets rid of the Wizard, demoralizing him by making him realize that he was Elphaba's father (the clue was a green vial of elixir he used to drink with his lover, which Glinda also saw being carried by Elphaba as a memento). Then she has guards take Madame Morrible into custody, and becomes ruler of the North herself.

Glinda announces to the crowd the news of the witch's death--this is where we came in!--and Elphaba again says goodbye to her friend as she leaves forever.