Alexander's day begins with gum stuck in his hair, followed by more calamities. Though he finds little sympathy from his family and begins to wonder if bad things only happen to him, his mom, dad, brother, and sister all find themselves living through their own terrible, horrible, no good, very bad day.

Olive, an average high school student, sees her below-the-radar existence turn around overnight once she decides to use the school's gossip grapevine to advance her social standing. Now her classmates are turning against her and the school board is becoming concerned, including her favorite teacher and the distracted guidance counselor. With the support of her hilariously idiosyncratic parents and a little help from a long-time crush, Olive attempts to take on her notorious new identity and crush the rumor mill once and for all.

Cody and Zack are approached to join the Gemini Project, a high-tech research center studying the dynamics between twins. Shockingly, they find themselves interconnected in a whole new way! When one twin experiences something, the other twin feels it too. This newfound revelation helps them see eye to eye for the first time, and it puts them in more danger than they could have imagined.

Powerful magic cast by Alex spells trouble for the Russo's. The kids must go on an adventure to save their family and their existence.

Mother and daughter bicker over everything -- what Anna wears, whom she likes and what she wants to do when she's older. In turn, Anna detests Tess's fiancé. When a magical fortune cookie switches their personalities, they each get a peek at how the other person feels, thinks and lives.

Top student Jane Ryan heads to Manhattan for a college-scholarship competition. Her rebellious twin Roxy Ryan goes along to crash a video shoot. But anything can happen - and does - in a romp involving a pursuing truant officer, a smuggler, hunkalicious guys and the girls' realization that when the chips are down, a sister can be the best friend of all.

Identical 9-year-olds from very different backgrounds: orphaned Amanda and wealthy Alyssa meet at summer camp and decide to switch places -- and play matchmaker between Alyssa's dad, Roger, and the kind social worker who cares for Amanda.

Hallie Parker and Annie James are identical twins separated at a young age because of their parents' divorce. unknowingly to their parents, the girls are sent to the same summer camp where they meet, discover the truth about themselves, and then plot with each other to switch places. Hallie meets her mother, and Annie meets her father for the first time in years.

Christina's love life is stuck in neutral. After years of avoiding the hazards of a meaningful relationship, one night while club-hopping with her girlfriends, she meets Peter, her perfect match. Fed up with playing games, she finally gets the courage to let her guard down and follow her heart, only to discover that Peter has suddenly left town. Accompanied by Courtney, she sets out to capture the one that got away.

High school hotshot Zach Siler is the envy of his peers. But his popularity declines sharply when his cheerleader girlfriend, Taylor, leaves him for sleazy reality-television star Brock Hudson. Desperate to revive his fading reputation, Siler agrees to a seemingly impossible challenge. He has six weeks to gain the trust of nerdy outcast Laney Boggs -- and help her to become the school's next prom queen.

On a Caribbean cruise, Jenny is marooned on a beach with her rock and roll idol. Deliriously in love with the idea of time alone with him, she manages to hide the fact that they're a stone's throw away from their resort.

Cady Heron is a hit with The Plastics, the A-list girl clique at her new school, until she makes the mistake of falling for Aaron Samuels, the ex-boyfriend of alpha Plastic Regina George.