Dimension 1 (John Smith 10)
Lucy is a 15 year old girl, who becomes a Plumber right around the beginning of the Clone Wars. She is assigned to Kevin's team, along with Eddy. She was originally a very shy girl, trying to keep her identity as a Lenopan, known as Sludgepuppies at the time, a secret, as the Lenopans and Plumbers are at war. Kevin finds out that she's a Lenopan, and keeps the secret, sympathizing with her as he had to hide his identity before. She became one of his most loyal soldiers.
When Kevin's, John's and Gwen's armies joined together, they were betrayed by Michael Morningstar, the Separatists attacking their camp. Lucy was the only person not knocked unconscious by the enemy's bomb, and continued to fight the Battle Droids, using her Lenopan powers. Inspector Milhil sees this, and being prejudice to "Sludges," he assumes she's the traitor, without any proof. Kevin goes to Lucy's defense, and the two are arrested.
Lucy is sentenced to public execution, while Kevin is thrown into the Null Void. John, Gwen and Ahsoka leave the Plumbers to rescue Kevin, then rescue Lucy during the execution. Afterwards, they go to Primus, where John and Kevin become mutated. Lucy joins Gwen, Ahsoka and Lucy as they go fighting the Separatists. They find their way to Mustafa, where they chase down the Separatist leaders. She saves Kevin before he falls to his death.
Afterwards, the girls and Kevin go to Wes Green, who tells them they need a witness to their innocence that had no association with them. Lucy agrees to transform into someone else, and is able to clear all of their names. She then joins Tack's army along with Eddy.
Lucy, Tack and Eddy respond to John's distress call, as the Earth has been taken over by the New Chess Pieces. She joins in the new War Games. Her first foe is Frightwig, who she defeats with ease. Her second battle was against Sonogram, who defeats her. She regains redemption when she defeats Ahsoka, who had become the enemy. In the 7th round, her final opponent is Kevin, who was in a zombie like state. She pressured John to allow her to fight him, to save him. She fights him, and allows him to absorb her energy, allowing her to break Kevin free. Their match was a draw.
She joins the heroes when they charge Phantom's Castle, and is separated from the others, along with John and Ultimos. They travel through different rooms, and after the disappearance of Ultimos, they find Kevin, who teams up with them. They encounter Darkstar, and defeat him, Lucy being immune to his attacks. John reveals that she was considered to fight Darkstar in the Final Round, and Hex fought Darkstar instead, winding up in Hex's death. She is defeated by Rob Lucci and captured.
After John frees everyone from Phantom's curse. Afterwards, she joins Tack and the others to fight Zombozo and reverses the effects of the De-Evolution ray.
She returns with Tack, Ahsoka and Eddy when John goes to them, joining for a mission. She, Eddy and John go to Viscosia to stop the revolution occurring. She reveals that she has a dream to end the war between her people and the Plumbers.
Later, John and Elektra go to Tack's ship again, as they get Lucy for a truce with the king of the Lenopans, Lucy telling them that name for the first time. They see her cousin Camille and Louie, Louie being the king. Since Lucy was a Plumber, Louie shunned her, as tensions between Lenopans and Plumbers has only escalated since the end of the Clone War. Louie orders his soldiers to attack them, as they retreat. Lucy is upset on the fact they are at war.
- General Kevin (first appearance)
- Secrets (John Smith 10) (first appearance of Sludge form)
- Lost Vendetta
- Reunion (John Smith 10)
- Framed (John Smith 10)
- Ultimate John (episode)
- Girl Power
- On the Run (John Smith 10)
- The Ultimate Battle Part 1
- The Ultimate Battle Part 2
- Set Up
- The Gathering (first re-appearance)
- New Chess Pieces (episode)
- War Games Revived
- The Second Round
- The Third Round Part 1
- The Third Round Part 2
- The Fourth Round
- Love and Hatred
- Friendly Fight
- The Fifth Round
- The Sixth Round
- 7 Knights
- Strength and Power
- Ghost of a Battle
- Before the Raid
- Castle Maze
- Gorge and Field
- Desert, Forest Edge and Plains
- Forest and Colosseum
- Darkness and Power
- Fifth Battles
- Army of Friends
- Double or Nothing (John Smith 10)
- A New Hero (John Smith 10)
- Goop Wars (first re-appearance)
Dimension 3 (Jane Smith 10)
Lucy is a main character of Jane Smith 10, becoming Jane Smith's best friend. They are always hanging out together, Lucy constantly encouraging Jane to become a hero, and on dating advice. She becomes concerned for her friend when she experienced side effects from Michael. It's eventually revealed that she is an Undercover Plumber, investigating Michael. However, Jane thinks that Lucy is spying on her instead, thinking the friendship was false. However, Lucy reveals the friendship was genuine.
Every episode since You've Got a Friend in Me.