Gehazi is Elisha's sometimes-faithful servant. He's usually a positive figure. In the stories he exists for the purpose of saying, "Gee whiz, Elisha! How're we gonna get out of this one??" when they're in a tight spot. And Elisha will be all like, "God will help." And then they get out of it, thanks to a miracle.
But at one point Gehazi tries to turn one of Elisha's miracles to his own favor, with disastrous consequences. After Elisha helps Naaman cure his leprosy, Elisha says Naaman doesn't need to give him any gifts. However, Gehazi runs ahead as Naaman is leaving and says Elisha changed his mind, thus fleecing Naaman out of some gifts.
But this ploy rebounds back on his head: Gehazi contracts the leprosy of which Naaman had just been cured and it remains in his family for generations. Nonetheless, he apparently learns his lesson and keeps working as a devoted servant of Elisha.