S01E21: Rescue the Tomboy!

Rie is being held captive though she does not realize it. She believes the man holding her is a friend of her father, Ken Makita. Lupin shows up to rescue her. Rie does not want to be rescued by Lupin and does not understand why he is trying to. Lupin's father was a friend of Rie's father. The "friend" is Jooji Takigawa; he is holding Rie hostage in an attempt to get her father out of retirement to do his bidding.