The movie begins with a young woman named Shelley Darlingson narrating and telling us what her life has been like. Apparently, Shelley was left in a basket on the steps of an orphanage when she was an infant. Her parents didn’t want her; they did however, want their basket back. Growing up in the orphanage was difficult for Shelley because she was an ugly duckling and never had a real family. Instead, she watched all her friends at the orphanage get adopted.
Fortunately for Shelley, she blossomed into a beautiful swan and soon became a Playboy Bunny, living at the Playboy Mansion with Hugh Hefner and his other bunnies. Life is pretty great for Shelley. She shops at expensive boutiques and all her expenses are paid by Playboy. She even has a really cute pink Prius to drive. One of her best pals at the mansion is Marvin, who mixes drinks for all the girls during parties and for breakfast. Shelley feels like the Playboy Mansion is her home, Hugh and the girls are her family, and she wants to live there “happily ever after.”
There are a couple things not going quite right in Shelley’s life, though. Firstly, Shelley wants to be Miss November. She has never been a centerfold before and this is her lifelong dream. Secondly, a fellow bunny has been giving Shelley a hard time out of jealousy. I can’t remember her name, so we will simply call her ‘Evil Bunny.’ Evil Bunny makes fun of Shelley for not being a centerfold, but Shelley is really too ditzy to realize how much of a threat Evil Bunny may be.
Things seem to be getting even better for Shelley though, because it’s her 27th birthday and the Playboy Mansion is hosting a giant party for her. Shelley secretly hopes that as a birthday present, Hugh Hefner will make her Miss November. She even has her “turn-ons” picked out . During her party, the girls all dance with one another and then a really tall cake is brought out. Shelley can’t reach the candle to blow it out, but Shaq lifts her up so she can make a wish and blow out the candle.
After a long night of partying, Shelley is woken by Marvin who brings her a special drink of orange juice with just a hint of chili pepper. (Making drinks is his passion.) Along with the breakfast he brings up for her, he brings a letter from Hugh. Shelley is hoping that it’s Hugh telling her that she’s Miss November. However, Shelley begins crying when she sees what it really is: a letter informing her that she is being kicked out of the mansion and she has only two hours to collect her belongings and leave.
Shelley is sure there is some kind of mistake. She runs to Hugh’s room to ask him about it, but he’s taken the rest of the bunnies on a trip to Las Vegas because “he’s not good with good-byes.” Crestfallen, Shelley gathers her belongings and leaves in the beat-up car she arrived in; not even her cat will come with her.
That night is a difficult one for Shelley. She has to spend the night in her car. While trying to brush her teeth in her car, Shelley spits out her window, which is spotted by a cop nearby. He comes over to write her a ticket and suspects she is drunk because of how ditzy she’s acting. He tells her she’s “going to need to blow on this” and begins to pull out a Breathalyzer, but Shelley misunderstands and thinks he’s telling her she has to give him oral sex. She starts going down and is immediately arrested and thrown in jail with several prostitutes, where she spends the night.
After Shelley is released the next morning, she overhears three girls talking about this party and follows them. They turn out to be college students and in a sorority. When Shelley sees the sorority house, she falls in love with it because it “looks like a mini-Playboy mansion!” She goes inside and meets with sorority sister Ashley, asking her if it’s OK for her to live there.
Ashley curtly informs her that although Shelley does look like an “older, sluttier” version of a girl they might allow into the sorority, she isn’t a student and they can’t allow her in. Depressed, Shelley wanders into a meeting in the next room, where all the house mothers are together. Shelley asks to be a house mother and thinks she would be great at it, but Mrs. Hagstrom, the house mother of the sorority Ashley belongs to, says that Shelley isn’t the type of person to be a house mother and that “this is not a brothel.”
Again, Shelley misunderstand and replies that she’s not interested in making soup. The rest of the house mothers completely spurn her, though. Dejected, Shelley leaves. One house mother follows her though, and informs her that a sorority known as Zeta has no house mother; their last one was hospitalized with hallucinations. This is great news for Shelley, though, who heads over to the Zeta house.
The Zeta house looks nothing like the house that belongs to Ashley and Mrs. Hagstrom’s sorority. It’s run down and when Shelley knocks on the door, part of the house falls off and hits her on the head, causing her to roll into some bushes. As she’s regaining consciousness, Zeta member Natalie runs out of the house following Dean Simmons. Apparently, Ashley’s sorority has complained because the Zetas never recruit any new pledges and should therefore lose their charter. Dean Simmons agrees and tells Natalie they have to get at least 30 pledges before mid-October or they will lose their charter.
After this, Shelley crawls out of the bushes and offers to be the Zeta’s new house mother. Natalie doesn’t see the point, though, because they won’t need a house mother if they aren’t even allowed to be a sorority.
Natalie goes inside and talks to her sorority sisters, an odd bunch of girls ranging from Lily (who is so shy she won’t even speak; she only text messages) to Joanne (a girl who wears a spinal brace). There is also Mona, a heavily pierced renegade with spiky hair; Harmony, who is seven months pregnant; and Carrie Mae, who looks, talks, and dresses like a man.
They are all talking about their predicament when one of the girls notices that boys are on their lawn. Boys always stay away from the Zeta house because they are so weirded out by the girls, so this is a surprise to Natalie who runs out of the house to see what’s going on. It’s Shelley, and she’s doing yoga on the lawn in her skimpy outfit, which has gathered a lot of male attention. Natalie figures that maybe if Shelley can teach them all how to get guys to like them and thereby increase their popularity, they may be able to get enough pledges to keep their charter.
Mona in particular is very against the idea and makes fun of Shelley for being so ditzy. Shelley is not deterred, though, and one of the first things she does is set up a car wash to earn funds for the sorority’s philanthropy efforts, or “phil-trophy” as Shelley calls it. While washing cars, some guys come over, one of whom is Natalie’s crush. Named Colby, he makes Natalie completely freak out and she doesn’t know how to act. Natalie offers him a drink from the hose, but Mona turns the water pressure up, which causes him to get shot in the face with water.
Shortly after this, Shelley meets a cute guy named Oliver who is putting up flyers requesting volunteers for the nursing home he runs. Shelley is intrigued by the idea of a nursing home, which reminds her of the orphanage she grew up in. She offers to bring the Zetas in to volunteer.
Because of Shelley, everything is changing up with the Zeta house. Ashley and her sorority sister Courtney continue to harass and tease them, even setting a pig loose in the Zeta house, but Shelley is undeterred. She and the girls repaint and redecorate the house, and then she gives all the girls makeovers. The girls, Mona especially, feel like they shouldn’t have to change who they are to get people to like them, but Natalie wants to do whatever it takes to save their charter, so they all buy new wardrobes and Shelley teaches them how to do their hair and makeup. They even make a Zeta calendar using themselves as models, which is wildly popular with all the guys on campus, all of whom buy two copies.
This isn’t going over well for Ashley and Courtney, who don’t even recognize the Zetas with their new makeovers. They don’t like that more girls are interested in becoming a Zeta than joining their exclusive sorority. They are even more upset by the Aztec Party that the Zeta girls host with Natalie as the virgin sacrifice because everyone goes to the Aztec Party instead of theirs.
Later, all the Zeta girls go to the nursing home where Oliver works to do their volunteer work. They all dance with the senior citizens and Oliver asks Shelley if she’d like to go to dinner. She really likes him, so she happily agrees.
Things don’t go so well on their date, though. Firstly, Shelley ends up with some really bad burns on her legs when she tries to seduce Oliver by standing over a steaming manhole cover. Then at dinner, she orders “Just one mahi,” instead of the mahi-mahi because she “isn’t that hungry.” What’s worse is that Oliver seems a little bit bored by her. She tries talking about her butt, but Oliver doesn’t seem that interested. Shelley makes things worse when, in an attempt to show Oliver how “in demand” she is, she lies and says they’d better cut the date short because she’s meeting another guy at eleven. Oliver is clearly offended and then leaves after paying for the meal.
Shelley doesn’t understand why her tricks didn’t work. Natalie figures out that maybe Oliver doesn’t mind it if girls are smart, which is baffling to Shelley who thought that intelligence was a turn-off to men. She immediately starts attending classes with Mona and Natalie, reads a lot of books, and starts spending a lot of time in the campus library.
After managing to get another date with a slightly reluctant Oliver, Shelley is determined to be what he wants her to be: smart. She wears a tweed sweater and a long skirt, pinning her hair back into a severe style. She even wears Natalie’s glasses in an effort to appear more intelligent, despite the fact that they distort her vision and make her dizzy. She also brings note cards on current events so that she can impress Oliver.
On the date, Oliver is impressed with all of Shelley’s knowledge on North Korea and current events and asks her if she’s thought about who she’s voting for. Confused again, Shelley says she isn’t sure, but that she definitely won’t listen to what Simon says and that she usually agrees with Paula. Then in embarrassment, she realizes Oliver meant the President. When their server then recognizes Shelley from Playboy, she is even more embarrassed and says she would never do anything like that. Flustered, she spills a drink and then uses her note cards to clean it up, which Oliver sees and asks her about. She pretends the cards are napkins and gets up to get more napkins to clean up the mess, but ends up tripping and bonking her head and getting gum in her hair. Completely humiliated, Shelley leaves.
Meanwhile, Hugh and the girls have just gotten back from Las Vegas. Hugh asks to see Shelley but Marvin says that Shelley is gone and she left a note for him. The note says that Shelley went to go work in Africa or some other foreign location. Marvin and the Evil Bunny worked together to get Shelley out of the house. Fortunately, Marvin ends up feeling bad about what happened. He feels so bad that he can’t mix drinks anymore. He admits what he did to Hugh who quickly calls Shelley.
Shelley gets Hugh’s call right after her second horrible date with Oliver, just as she’s walking up to the Zeta house. Hugh tells her that he wants her back at the mansion, that he wants her to be the Miss November centerfold, and that they’ll do a long European tour to promote it. At first, Shelley is happy, but she remembers the Zeta girls and tells Hugh she can’t do it. She doesn’t want to leave her family.
Unfortunately, inside the Zeta house, trouble is brewing. They are looking through pictures of girls and trying to decide who they should pick to be in their sorority. They are acting really bratty and making catty remarks about all the girls and Lily speaks up for once, saying she hates what they’ve become: just like Ashley and Courtney’s cliquish sorority. They realize that in spite of their makeovers, they don’t like how much they’ve changed and they start getting angry with Shelley.
When Shelley walks through the door, they immediately pounce on her and start asking her why she had to mess everything up for them. Heartbroken, Shelley tells them that she’ll leave if that’s what they want. She walks out the door and no one stops her.
The Zeta girls decide to find a happy medium. They will be themselves and still try to look nice at the same time, but without all the hair extensions and fake eyelashes. They also decide that they will randomly select 30 girls to join the sorority, instead of picking selectively. Colby, Natalie’s crush, really likes her the way she is, it turns out. They become boyfriend and girlfriend.
Then one day, Lily goes out to mail the invitations to the 30 girls randomly selected to join the Zeta house. Ashley, however, uses a cute guy to distract Lily and then throws away the invitations and mails some decoys instead. On the day when the pledges are supposed to show up, no one comes. Lily and the rest of the Zeta house girls realize what happened and realize they are about to lose their house.
Meanwhile, Shelley is on a photo shoot for Miss November. In the middle of the shoot, she realizes she doesn’t want to be a centerfold. She just wants to be back with her family, the Zetas. As she’s leaving, she runs into Natalie and the Zetas who want her back too. Their house is already on the auction block, but Shelley thinks there is still time to save it.
Ashley and Courtney’s sorority is going to try to buy the Zeta house to keep all the new pledges in. Shelley comes in and makes a speech about not just living for the external, because that doesn’t last. She then asks for 30 right then and there to commit to pledging Zeta so they can save their house. They quickly get 29 pledges and Harmony comes in with her newborn baby. They try to get the baby to count as number 30, but Dean Simmons won’t allow it. Ashley is frustrated and screaming at Dean Simmons to pound the gavel because the Zetas failed. At the last second, Courtney says that she wants to pledge Zeta and leaves Ashley.
The Zetas all happily go back to their sorority house where they cheer and laugh. Shelley is happy, too, except for how things turned out with Oliver. Suddenly, she sees Oliver standing in the house, holding roses. Natalie had told him Shelley was back. Shelley admits to Oliver that she was in Playboy, but he says he doesn’t care. He just wants to get to know her the real her.
So the Zetas get to keep their house, Shelley and Oliver start dating, and Shelley finally gets the family she always wanted as the Zeta’s house mother.