Go to the Duck Village Inn. Go to the farthest room from the screen and talk to the kid. You will have to help him with something. After that, he will go to Lake Castle. After you name the castle, go to elevator and go to the floor with the detective/storehouse and find Kidd. Talk to him and chose "Scout". He will scout for a character for about 300 Potch. He will hint about the character's location and/or how to get them. This works with Geddoe, Chris, and Hugo.

You can only recruit characters after visiting Budehuc Castle. Also, Budehuc Castle is the only place where you can change your party.