Twin sisters Liv and Maddie finally reunite when Liv returns home to Wisconsin after starring for four years in a hit musical television show in Hollywood. The Rooney sisters quickly realize their polar opposite personalities put their unbreakable twin bond to the test. While their parents play referee between Liv, a cool, confident, social butterfly who loves to sing, and Maddie, a smart, athletic, high school basketball star who opts for high tops over high heels, brothers Joey and Parker seize the opportunity to capitalize on the chaos and get away with as much as they can.

Maddie is named captain of the girls' basketball team just as the school principal announces he is cutting funding for the program. Determined to change his mind, Maddie voices her concern to the principal, only to realize her team has abandoned her. Frustrated with her lack of leadership skills, Maddie turns to Liv to help her earn the team's respect. Meanwhile, Parker and Joey are challenged trying to find a bevy of tarantulas that escaped after Parker brought them home from school unbeknownst to their mom.

After Liv realizes just how much Parker has grown up while she was away, she volunteers to supervise his sleepover in hopes of reconnecting with him. But when all her activities backfire and start to embarrass Parker in front of his friends, Liv has to up her game in order to impress her little brother. Meanwhile, Maddie and Willow work on a school project, and Joey and Pete go on a road trip to the Pastrami Palace that leads to a wild night of fun.

Liv has a difficult time making friends at school so Maddie steps in to help.

When Joey is too nervous to talk to the new girl who he likes, Maddie decides the best place for him to practice talking to girls is at the high school dance–when everyone is in costume. Meanwhile, Parker booby-traps the house to protect one of the family’s most prized Halloween decorations from being stolen.

Liv wants to back out of being a celebrity judge at a skateboarding competition after her boyfriend, a skateboarding pro in town for the competition, breaks up with her via text. Meanwhile, Joey and Parker are ecstatic when they meet a masked skateboarding pro who is famous for his massive wipeouts.

When Liv decides to volunteer at the senior center where Maddie works, chaos ensues and the seniors get the girls involved in a rowdy game of dodge ball to claim their turf.

Ridgewood High is hosting the annual "Brain Olympics", and Joey is intent on forming a team in hopes of winning. Liv, in an effort to shed part of her girly image, convinces Joey to let her join the team. In competition, each team has to build a Rube Goldberg machine, but when Joey thinks she is not clever enough, Liv decides to build her own. Meanwhile, Maddie holds a yard sale to raise funds for the French Club's trip to Montreal, and a priceless childhood memory accidentally gets sold.

Liv and Maddie try to plan their sweet 16 party but complications arise.

The annual Stevens Point Holiday Spectacular is coming up, and Liv is asked to host the televised event. When Liv discovers the little girl she's asked to perform with shares the same strong desire for the spotlight, trouble ensues. Additionally, Pete and Maddie are in charge of decorating the city's Christmas tree, but the power goes out amid Liv's performance. Meanwhile, Parker swindles money from Joey while dressed as Santa and an elf in order to purchase an expensive present he suspects no one will gift him.

When Maddie fails her driving test and Liv needs help trying to get a part in a sci-fi play, they decide to switch so Liv takes Maddie's driving test and Maddie auditions for Liv. But when Maddie accidentally yells, "Bam! What!?" Joey and Parker realize it's her and not really Liv, and Liv wrecks the car during Maddie's driving test.

Maddie and Pete sign up in a basketball Tournament.

When the kids overhear their parents' conversation, they mistakenly believe they are moving.

Maddie and Willow are excited to try out for the school's varsity softball team, but Maddie, the catcher, realizes that Willow, the pitcher, is in a slump because she can't stop thinking about Joey.

Maddie and Karen take part in a historical society's annual mother-daughter weekend of pioneer living.

In an effort to help Maddie bring out her “girly side,” Liv gives her a pair of the most comfortable high heels ever made.

Liv is told that the coveted role of Tristan in “Space Werewolves” has been narrowed down to herself and two other famous actors.

Maddie anxiously waits for a letter from the Junior Olympics to arrive to find out if she is invited to try out for the basketball team.

Maddie gets jealous when Liv's best friend from Hollywood visits and flirts with Diggie.

Liv's new music team makes a big mistake that causes her latest single to become a viral hit for all the wrong reasons.

To prove to the skeptics that she is meant to star in “Space Werewolves,” Liv agrees to do all her own stunts, not realizing exactly how complicated they are. Maddie tears her ACL and needs surgery, therefore not being able to play in the championship or go to the Junior Olympics.

In the season two premiere, the family is getting ready to compete against one another in the Wisconsin Cheddar-Brat Fest. Ironically, Liv’s premiere of “Space Werewolves” is on the same night.

Maddie is recovering from her knee injury and decides to take up a new hobby. Meanwhile, Karen asks Liv for advice on dressing cool, which results in a mother-and-daughter fashion face-off.

A magical amulet turns the twins into triplets, producing a frightening sister named Helga; Joey and Parker use the amulet to clone themselves.

Liv becomes friends with a Korean pop star after she visits America to study Liv’s acting for the Korean version of the hit show, “Sing It Loud.”

Liv tries to play matchmaker and help Willow win over Joey's heart at the school dance.

When Liv is offered the lead in a basketball movie, Maddie and Willow volunteer to transform her from a clumsy athlete to a basketball pro.

Liv co-hosts and performs at a New Year's Eve party and when a secret is revealed on live TV, it causes Maddie to question her long distance relationship with Diggie.

Joey and Parker have finally reached the point of no escape and have to clean their inexplicable filthy room. When they try to trick Liv and Maddie into cleaning it for them, the girls fight back with an even better ruse.

Maddie is devastated when she loses her twin charm bracelet that Liv had given her; however, when Liv tries to make her feel guilty, Maddie decides to teach her a lesson. Meanwhile, Joey's feelings are hurt when Parker gets a new cool older brother.

Liv, Maddie and their friends confront a fellow schoolmate who has been giving them numeric ratings based on looks.

In order to get out of a mother/son pageant, Parker intentionally gets up to mischief to get detention. Meanwhile, Pete plays nurse when Liv and Maddie get sick at the same time.

Liv is filming the "sequel" to the muffler commercial she did when she was six. Meanwhile, Maddie is feeling nervous about her knee as she prepares for her first game back.

Liv meddles with Diggie's "meet-a-versary" gift for Maddie and Parker concocts a new face cream for Karen.

During a neighborly feud with the Dippledorfs, Liv rekindles an old friendship with Holden Dippledorf. Meanwhile, Joey becomes fascinated with a new member he meets at his weekly Intergalactic Council meeting.

Liv must finish a 6th-grade project to avoid taking summer school. Joey gets Maddie to teach him how to be a jock to impress a girl.

To raise her grade in Mr. Clodfelter's home economics class, Maddie must win the Plate Off and defeat the class master chef, Artie. Meanwhile, Joey convinces Pete to sponsor his made-up clubs at school.

Liv realizes she has a crush on Holden, but Andie asks him to prom before Liv can. With Diggie away, Karen arranges for Rooney cousin Craig to take Maddie to prom but when he arrives they realize that he has reinvented himself into an illusionist named Kraghh the Insidious.

Diggie returns from Tundrabania, but he and Maddie have trouble reconnecting. Joey tries to solidify his relationship with Diggie through the Tundrabanian sport of Flugelball. Meanwhile, Parker attempts to teach his new unlikely friend Dump Truck how to ride a bike.

Liv rallies together a band, The Dream, to compete in the upcoming Stevens Point Battle of the Bands contest. Joey and Artie form a band too, but they can't seem to agree on anything.

Liv and her band mates are stumped and can't agree on a theme for their new music video. They enlist Parker to shoot the video with his new camera and Diggie enthusiastically signs on to join his crew.

Liv and Holden share a special moment as they rehearse for an upcoming performance. Meanwhile, Reggie ditches Parker for a chance to play basketball with Maddie.

Ridgewood’s mascot has been vandalized, and the Rooney’s all become suspects. Meanwhile, Parker has the day off from school and gets into trouble at home with Reggie.

Maddie and Diggie try to "out-fun" each other at a local music festival as Liv tries to help Andie get over her breakup.

Before he leaves for Australia, Diggie needs to tell Maddie how he feels. Meanwhile, Parker, Reggie and Evan swear they will remain on the couch until the new season of Linda and Heather is released.

While Joey and Maddie try to catch Diggie before he departs for Australia, Liv covers for Maddie at home. But when Diggie shows up at the Rooney house, chaos ensues, reminding Parker of his favorite soap opera drama. Meanwhile, Liv gets a call from her manager telling her she landed a coveted role in a new TV show "Voltage."

Maddie enlists Liv's help to build a giant Paulie Porcupine head for the Homecoming parade, but Joey and Parker accidentally destroy it while playing around with a stunt-prop from Liv's TV show, "Voltage."

Casting is underway for Liv's co-star in "Voltage" and some familiar faces show up for the auditions. Meanwhile, Karen arranges a "cleansing ceremony" for Maddie to help her let go of her feelings for Diggie.

Maddie and Willow join in on the Senior Scare, in which high school seniors scare middle school students; Liv and Joey head to New York.

Liv tries to help her new co-star Josh feel more comfortable in Stevens Point while the rest of the school prepares for Cowbell Week, a Stevens Point tradition.

Joey invites three girls over to watch the "Lover's Comet;" Grandma Janice presents Liv with an award but something seems off.

When Willow earns a scholarship that Maddie really wanted, the besties get into a huge fight. Then, when Joey accidentally breaks Liv's toe and tries to make things better, he ends up making it even worse.

Liv gets upset when an interview focuses on her appearance instead of her acting. She enlists her friend Kristen Bell to help her change the conversation. Meanwhile, Maddie must hunt down a lost library book or else she won't get her final grades.

Liv invites her “Voltage” director and crew over for the Rooney’s traditional Christmas Eve dinner but is forced to enlist Artie’s help to prepare the famed meal. Meanwhile, Maddie and Willow’s gift exchange takes a surprising turn.

When Parker gets bumped up a few grades, he starts attending high school with Liv, Maddie and Joey! The older siblings now have to deal with him being good at everything.

A new coach arrives to take charge of the girls' basketball team and immediately butts heads with Maddie. Meanwhile, when Liv agrees to help Parker with his art project, her date with Holden takes an unexpected turn.

Joey and Parker hold strong beliefs that the Voltage set is haunted; Josh finds an excuse to spend time with Maddie.

When Liv needs to learn French for an upcoming interview, her mom decides to immerse her in the language and culture. Meanwhile, Maddie is thinking about dating again.

"Voltage" is taking up all of Liv's time, but when The Dream is asked to reunite for a fundraiser, Liv is determined to make it happen. Meanwhile, Maddie tries to figure out where to go to college.

Maddie and Josh go on their first date. Liv and Holden try to help Parker pass his show choir class.

A reporter mistakes Maddie for Liv while she's on a date with Josh. Maddie doesn't want Diggie to hear the news from the press, so she asks Liv to play along.

With Diggie’s return, Maddie is torn between him and Josh. Meanwhile, Liv is asked to plan a wedding in under a week when Gemma and Johnny Nimbus decide to get married.

Liv is not too happy when Joey lands a part on “Voltage.” Meanwhile, when Karen finds out that Andie's dad, Mr. Bustamante, disapproves of Dump Truck, they team up to change his mind. Josh has been really depressed since his split with Maddie and Liv realizes having Joey around cheers Josh up so gets him a small role in Voltage, but he takes it too far.

Liv realizes that Voltage is moving their set to Los Angeles and she must pick to either move to California with the show or stay home and go to college with Maddie. Joey finally realizes that he likes Willow back and he needs to tell her this before she leaves to California for training camp.

In the season three finale, Liv and Maddie get into a big disagreement while trying to figure out if they'll be together for the next four years or be going their separate ways.