S1E10 : The Weirdest Guy Ever! Jango the Hypnotist!

When trying to convince his rich friend, Kaya, to give the Straw Hats a ship, Usopp is told to stay away from her by her caretaker, Klahadore. However, when Usopp and Luffy later see him conversing with a strange man, they learn of a plot to kill Kaya.