X-Factor - Volume 9: Invisible Woman has Vanished — Peter David

Collects X-Factor #200-203. X-Factor has relocated back to New York, and their first client is a keeper: Franklin Richards, whose mom has disappeared and who figures that the premiere detective agency in the Marvel Universe has the best chance of finding her. Except Reed Richards doesn't seem especially cooperative in helping them locate his missing wife. What is he hiding, and does it have anything to do with the coming Darkness?