S4·E2 Futureshock!

During a cheer leading practice, Mandy breaks a nail and has to work as a TV reporter to kill time for her nail to grow back. Meanwhile, during a clean-up of Jerry's office, the spies discover a gadget that accidentally sends them twenty years into the future. While there, they soon uncover the horrifying truth that Mandy rules Beverly Hills and she plans to 'Mandify' everyone! Teaming up with their future self, the girls must stop her and stop it from ever happening. The spies arrive to Future WOOHP and return to present by the time machine. In the end, the spies put the recreate nails in Clover's school wardrobe. Mandy sneaks in and takes the recreate nails. She's got normal nails again and decides to quit from work of TV Reporter. In the b-story, Mandy is upset because what she will do with her broken nails. Villain: Mandy.

Note: This episode indicates that the timeline for season 4 occurs in 2005 because they say that when it's 2025, it's 20 years into the future.