Lucy appeared in the episode Queen of the Serpentine!. In the anime, it was mentioned that she does not teach her Pokémon defensive moves.

Before battling Ash, she had rescued his Pikachu from Team Rocket with her Seviper, defeating Jessie's Seviper in the process.

In the battle, Ash started off by using his Donphan against Lucy's Seviper. For a while, Lucy seemed to be having the upper hand despite the type disadvantage. However, Ash managed to turn the tables on the serpent Pokémon by using Donphan's Rollout to counter Seviper's Flamethrower, knocking it out of the battle.

Lucy then sent out her Milotic which easily took out Donphan with just a single powerful Hydro Pump attack. Left with no other choice, Ash decide to use Pikachu. However, again, despite the type disadvantage, Lucy almost managed to defeat the electric-mouse Pokémon by treating it to a barrage of Hydro Pumps and Twisters. She even used paralysis to her advantage by using Facade. Ash finally managed to defeat it and win the match when he innovated a move by making Pikachu jump inside one of the twisters and using a spinning Volt Tackle.

In addition to her preference of serpentine Pokémon, Lucy also seems to have a soft spot for squinty eyes, as she was shown to keep several pet Pokémon at home, all of which had squinty eyes. She develops a crush on Brock due to his squinty eyes.

Lucy in the anime is very different from her game self personality wise. In the anime, though quiet, Lucy seems to be a rather a nice person, allowing Ash to battle her even though the Pike was closed that particular day. She also congratulated him on his victory. In the games, however, she is narcissistic and seems to be very irritated when the player defeats her. Her change of attitude in the anime can be attributed to her crush on Brock and a desire to impress him.