As these things go, with G.I. Joe: Retaliation making all of the money this weekend, Variety reports that Paramount is already starting to plan another sequel. Retaliation both cost less than the first Joe movie and is on pace to earn more. (At this rate, the twentieth Joe movie will be just the Rock playing with G.I. Joe toys and it'll make $40 billion.) There's no word on what this third movie will be about, but we assume it'll start by summarizing the last one, end with the Rock squaring off against Cobra Commander, and the middle will be a mishmash of ninja flips and explosions.