Sakura Avalon discovers the magical Clow Book in her father's basement. After accidentally breaking the seal and releasing the cards, the Guardian of the Clow Cards, Keroberos (Kero), appoints her as Cardcaptor.
Sakura is still coming to terms with her new role as a Cardcaptor. Her best friend Madison quickly learns of her secret and takes on the role of battle costume maker. The two, along with Kero, are soon confronted with the Shadow Card.
A trip to the aquarium leads to trouble when an employee is pulled into a whirlpool. Sakura and Kero suspect the Water Card is behind the incident. Sakura must use her strongest allies to capture this feisty card.
While doing chores around the house, Sakura discovers two Clow Cards: Wood and Rain; however, failing to properly seal the cards, they escape in the house and create chaos.
A new toy shop opens and with it comes trouble with some of the merchandise, something the owner is no stranger to: purchased toys make their way back to the store. It's up to Sakura to determine which Clow Card is behind the phenomenon.
A ghostly specter is frightening Sakura and her friends. Each student sees something different--from creepy creatures to food. Sakura sees her deceased mother and realizes the Illusion Card is behind the scary sightings.
Sakura witnesses a young child, Alex, trying to alter a painting they claim has been painted over. Investigating the gallery at night, Sakura, Madison, and Kero encounter Alex again - and the Silent Card.
A new student arrives at Sakura's school. He also happens to know about the Clow Cards and insists she give the cards to him. The two confront the Thunder Card together, further driving a wedge between them.
Sakura ruminates on her encounter with Li and the Thunder Card. Later, they clash as the Sword Card appears--and takes control of Rita. Can they release Rita from the card's power without hurting her?
It's sports day at the school, and an unexpected reunion takes place--Sakura's dad and Madison's mom. The two were best friends with Sakura's mom and had a falling out many years prior. With the help of the Flower Card the two reconcile.
Madison asks Sakura to come to her house to help with a problem--a special box belonging to her mother, Samantha, no longer opens. The Lock Card has become extra protection for the valuables kept within the box.
Sakura finds herself performing the same music test three days in a row as the Time Card makes its appearance, causing the day to repeat itself. After many failed attempts, the trio are able to overcome this tricky Clow Card.
A trip to the zoo proves eventful when the Power Card shows its abilities. With the help of elephants in a game of tug-of-war, Sakura takes on this tough Clow Card.
Tori's class is putting on a play, but things go awry when the Mist Card appears and starts destroying the set. Can Sakura save her brother and his classmates before the set comes crumbling down?
After Li successfully captures the Storm Card, Sakura and Kero have a big fight. Kero leaves the house and makes a new, young friend, named Anika. Sakura searches frantically for Kero, spotting him--along with another Clow Card.
Sakura, Tori, their dad, and Julian spend a week at a summer house. Sakura visits her maternal grandfather who lives nearby and learns more about her mom.
An environmental studies field trip to the beach proves frightening when students begin disappearing while on an ancient shrine walk. Sakura and Li track down the Erase Card that's haunting a cave where their classmates vanished.
While scrambling to finish her summer homework, Sakura spends the afternoon at the library to work on her book report. The book she seeks, which Li is also reading, keeps moving around the library all on its own.
Much to his dismay, Li's childhood friend, Meilin Rae, moves to Readington. To prove that she too can capture cards, despite having no magical lineage, she takes on the Fight Card.
A school marathon takes an unexpected turn when the Loop Card extends the race for Sakura, Li, and Meilin. They are trapped in the loop until they can find where the circuit repeats.
Sakura's dad has been busy preparing for an important lecture. Sakura and Madison decide to visit him and his team and provide refreshments. To their dismay, the Sleep Card runs amok, putting Aiden's students to sleep.
In the excitement of the upcoming music competition, rumours fly of a ghostly voice singing at the school at night. The Song Card has found a beautiful voice to impersonate. With Madison's help, Sakura is able to capture the card.
Sakura goes missing when she investigates the presence of a Clow Card at home. The Little Card shrinks the Cardcaptor and she has to try capturing the card at the disadvantage of her miniature stature.
Chaos ensues when a young girl appearing to be Sakura's double runs amok in Readington. To make matters worse, her doppelganger harms Tori. It's up to Sakura to save her brother. She also learns a new way to use the Clow Cards.
With the arrival of a new teacher, Ms. MacKenzie, so too appears another Clow Card--the Maze Card. It shifts and moves people around, and magic is no use against it. With the help of Ms. MacKenzie, Sakura, Li, Madison, and Meilin escape.
Sakura and Li track down a Clow Card to the shrine where Ms. MacKenzie's helping out her dad. Sakura's transported back in time and observes Tori and Ms. MacKenzie meeting. Li frees Sakura and they capture the Return Card.
When Twin Bells receives a shipment of magic cards that resemble Clow Cards, Sakura makes a disturbing discovery: one of the cards was a true Clow Card. Can she track it down before its buyer gets hurt?
The Sweet Card makes a mess of the home economics classes, as it causes the baking to be too sweet. While trying to bake their assignments for a second time, Sakura and Li capture the playful card.
While trying to capture the Dash Card, it escapes and is taken in by a Jessie, a classmate of Sakura. When Sakura learns of the bond between Dash and Jessie, she refuses to capture the card. It's up to Li to ensure its capture.
When Nikki finds an storybook in which she can add to the story, her imaginings come to life. While trying to track down the card, Sakura and company stumble upon another card. It comes to Sakura's aid when she needs it most.
While capturing the Switch Card, Kero and Li swap bodies. They have to stay in each other's form for 24 hours before they can be reunited with their correct bodies. The trick? Not letting on that they aren't who they appear to be.
A class trip to the ice rink goes awry when the Freeze Card lowers the arena temperature and everything begins turning to ice. Sakura and Li work together to capture the escaped card before everyone freezes.
The first-ever Readington Quiz Competition is being held, with Sakura partnering with Julian for the challenge. After a warning about the full moon, a fall relating that astral body leads the pair into minor trouble.
Sakura begins to suspect who the figure in her dream is and wants to prove herself as she grows as a Cardcaptor. While planning to talk to Li, the Firey Card springs up at the winter carnival.
