Uncanny X-Men - The Extremists (2007)

Collects Uncanny X-Men (1963-2011) #487-491.
The X-Men are back from space, but the team is shattered, broken and separated. Then, attacks in the Morlock Tunnels immediately grab the X-Men's attention. What do these attacks have to do with the future of the mutant race? Maybe Storm can get to the bottom of all this!