The film begins with 18-year old Grace Ann Bennett (Selena Gomez) working at a diner with her best friend, Emma Danielle Perkins (Katie Cassidy), a high school dropout. Grace adds another pinch of change to her jar marked Graces Fund for Paris.At graduation, the valedictorian is speaking when Meg Kelly-Bennett (Leighton Meester), Graces uptight older stepsister, comes in late. Everybody turns to look, embarrassing Meg. That night, at dinner, Graces stepdad (Brett Cullen) announces that he has paid for all the girls to go on a trip to France. Meg, who does not want to go with the girls, refuses. She states that all her life she wanted to be friends with Emma Perkins, and now shes stuck on going on a soon-to-be-disastrous trip.The trip proves to be horrible, as they have been ripped off for a small suite and have a small amount of time to visit so many places. They get left behind by their tour guide and trudge through the streets as it rains, seeking coverage in a posh hotel.As the girls dry up and Grace goes into a stall, Cordelia Winthrop-Scott, a spoiled British heiress (Selena Gomez) comes in, complaining on her phone about a charity event she must attend. Meg and Emma, after Cordelia leaves, try to convince Grace that they look exactly alike, but Grace does not believe this until they return to the lobby and everyone mistakes her as Cordelia.The girls spend the night in Cordelias suite while Cordelia leaves to go elsewhere. As they leave the next day, they are attacked by hungry paparazzi with their cameras into Cordelias limo. They realize they are on their way to Monte Carlo.The next day, the girls meet Theo, the son of the philanthropist hosting Cordelia. Theo thinks of Cordelia is a snotty brat, and is cold to the girls. He escorts them to a ball, with Mika's "Love Today" is playing in the background, where Grace encounters a problem as she meets Cordelias suspicious Aunt Alicia. Emma, seeking the wealth she always wanted with her boyfriend Owen, dances with a prince.The girls return to the hotel. That afternoon, the girls relax on the beach. Emma and Meg make snide remarks to each other, Meg accusing Emma of wasting her life by dropping out of school to model, saying nobody ever missed her. Emma responded by saying Megs mother probably didnt miss Meg either, causing Meg to storm out and bump into Riley, someone she met while in France.Afterwards, Grace plays polo with Theo. Aunt Alicia, suspicious, calls Cordelias phone. The real Cordelia picks up, and later, Aunt Alicia confronts Grace, thinking that Cordelia has hired a lookalike to take her place while she parties wild. She threatens Grace, stating that if her plan foils, she will have her arrested for identity fraud. After the game, Theo takes Grace to a special place of his, and together they watch fireworks.At the same time, Emma is dining with the prince she met the night before. They are on a boat where a party is going is on, with Mika's "Relax (Take It Easy)" is playing in the background. She finds him to be obnoxious and arrogant as he makes a snide remark about her picking up the dishes, telling her there are people for that. She replies just as coldly: I know, grabs her things, then goes off to a different part of the boat.Meanwhile, Meg is with Riley. He tells her that he used to be a talented rugby player, but an injury kept him in the hospital for a year. He enjoys traveling. Meg opens up to him about her mother, who was hospitalized for almost two years. She tells him that she wanted to scream when people showed sympathy way too much, and Riley replies that maybe she should. She doesnt, but the two share a passionate moment.As the girls have fun, Owen, Emmas boyfriend, a truck-loving football player, comes to France to look for Emma. When he hears that the girls are in Monte Carlo, he goes there to win Emma back. Everything begins to crumble with Cordelias unexpected return. Theo, thinking that Cordelia is Grace, kisses her, causing him to get slapped.Cordelia then goes up to the room and out on the balcony, where, the girls, after cleaning the room, hid. Cordelia goes back in the room and throws away a half-eaten apple left behind by Meg, and then sees a newspaper about the girls in the trash can. She runs to go see if the prized Bvlagri necklace planned to be sold at an auction is still there. It is not, as Meg put it in Rileys backpack for safekeeping. Cordelia then calls the police.The girls chase after Riley, now on his way to Italy. They are too late, and go back to the hotel. Grace, in a moment of sheer determination, kisses Theo, causing him to tell a bellboy: I dont understand women. The manager asks if she requested the cops, and Grace tells him no. The three then proceed up to the suite, where they encounter Riley, who returns the necklace to them. The three confront Cordelia with the necklace now in their hands.Furious, Cordelia calls the police again, but Emma ties her up in another room while the police come. They say they heard screaming, in which Meg replies that Grace was so happy she found the necklace. The police go back down, and so does Meg. Upstairs, Emma meets with Owen.The two reconcile just as Cordelia escapes. By now Grace and Meg have gone to the charity event, which Cordelia crashes. She tells everyone that Grace is an imposter, shocking Theo. Cordelia demands Grace arrested, but nobody cares as her aunt Alicia has bought the necklace for $6 million Euros. Theo leaves. After the trip of a lifetime, Meg climbs atop an ancient ruin with Riley, and together they scream.At a place of their own, Emma cooks while Owen installs the dimmed lights she always wanted, and the two laugh. Grace, volunteering with children in Romania, travels to the post office just as Theo sees her. The two introduce themselves again, smiling.The credits role playing Mika's "Blame It On The Girls" and ending with Selena Gomez & The Scene's "Who Says".
Output: Question: Who is Riley?, Answer: Australian backpacker