Superman/Batman (2003-2011) #49

In 'The Search for Kryptonite' part 6 of 6, The Man of Steel must confront an old friend who's harboring Kryptonite and threatening to set off 'Kryptonite dirty bombs' around the world. Now, the World's Finest has to race to prevent detonation before Earth is made uninhabitable for all Kryptonians!