Aggressively middling sequel goes through the motions to such a degree that even Downey Jr. can’t save it.  Miscast Mickey Rourke shoplifts Malkovich’s moose-and-squirrel accent from Rounders.  And somebody somewhere should be cleaning up litter on the 105 with a pokey stick for wasting Sam Rockwell like this.  Only real bright spot:  Scarlett Johansson makes a damn fine Black Widow; her scenes feel like she wandered in from a better movie.