Jessie's Frillish first appeared in New Places... Familiar Faces!, debuting along with James's Amoonguss when Team Rocket attacked Ash and his friends for the first time since their "Operation Tempest" and temporary retreat back to Kanto.
When Ash and friends were helping the rookie Trainer Nanette to gain some experience, Team Rocket surprised them, sent out their new Pokémon, and used a combination of Mist and Stun Spore on them and their Pokémon, reducing the visibility to almost nothing and paralyzing Iris's Emolga and Cilan's Stunfisk at the same time, thus leaving Ash alone to face Team Rocket with Pikachu. After Amoonguss had successfully knocked Pikachu out, Jessie had Frillish use Psychic, lifting Pikachu into the air and towards Team Rocket's mecha. However, thanks to the distraction provided by Nanette and her Tepig, Pikachu was freed, although Tepig got caught in the process. For a getaway distraction, Team Rocket fired a combination of BubbleBeam and Hidden Power, which, much to their surprise, was endured by Ash's Unfezant, followed by an Air Cutter and an Aerial Ace to defeat Frillish and Amoonguss.
Frillish reappeared in The Name's N!, where Jessie sent her out after catching Pikachu. She distracted Ash from holding on to his Snivy when Snivy used Vine Whip to grab onto their balloon. Frillish once again battled Unfezant and used BubbleBeam on her, but Unfezant dodged and used Aerial Ace to free Pikachu. Pikachu joined in the battle and tried to finish off Team Rocket with Thunderbolt, but Amoonguss's Stun Spore paralyzed him before the attack completely blasted them off. Frillish was taken out along with Amoonguss by Unfezant's Air Cutter which slammed them into Team Rocket's balloon causing it to be blasted away.
After Team Plasma took control of Meowth with their machine in Meowth, Colress and Team Rivalry!, Jessie and James decided to attack their friend in order to get him out of the trance. After Amoonguss used Stun Spore to paralyze Meowth and Body Slam to incapacitate him, Frillish brought Meowth back to Jessie and James with Psychic. Having Meowth out of Team Plasma's control, Team Rocket managed to get out of their headquarters using Frillish's Mist.
Frillish was given away to Giovanni for Team Rocket in The Dream Continues!.