S1·E34 A Reversed Trip

Commander Masaki sends Bikel and Walter on vacation in Yamanashi Prefecture (at the base of Mount Fuji) so that they can study human interaction. While on the way there, they run into a little old lady who seems to believe that the only thing you can rely on in the world is money. When she's kidnapped and held for ransom, Bikel and Walter have to shift into high gear to rescue her and they're in for an explosive conclusion.