One Piece Chapter 26, page 10: CAPTAIN KURO'S PLAN

Jango sighs, "OH WELL.... YOU GUYS.... HEARD EVERY-THING...." He pulls out his ring pendulum and swings it: "TAKE A LOOK AT THIS PENDULUM... WHEN I SAY ONE, TWO, JANGO, YOU WILL FALL ASLEEP... ONE.... TWO...." Usopp panics, shouting, "AH! THAT! HE'S GOING TO USE THAT TO KILL US!! IDIOT, HURRY AND HIDE!" Luffy, completely unfazed, just stares blankly and asks, "LOOK AT WHAT?"