smallville Season6 Episode4

Wearing a valuable necklace given by Lionel, Martha goes to a party held by Lionel Luthor. During the party, a mysterious man disturbs the crowd with an arrow before grabbing Martha's necklace and runs off. Clark, after investigation, finds out that the thief is Oliver Queen, a billionaire who has stolen valuable things not only from Lionel, but also from other insidious rich people, and then donates to charity. Clark is impressed and helps Oliver to escape before Lois can unveil his identity. Grateful for Clark's help, Oliver gives the necklace back and they have a conversation about how to use Clark's power to help the world.