David Grant Wright

Someone from Derek and Addison's past arrives in Seattle and shakes things up. Meanwhile, Burke learns about Christina's secret and, after a visit with her mother, Meredith looks into more of her family's dirty laundry.

The BAU looks to outsiders for clues when three college athletes disappear the night of a pep rally; J.J. is instrumental in moving the case forward.

Lightman tries to prove that a brilliant and charming psychology graduate student is a psychopath; Torres and Loker investigate a UFO sighting.

Christina drops a bombshell on Michael; Lincoln runs into a deadly trap; T-Bag tries to prove that he can be a Company man.

Naomi seeks Fife's help with William's experimental treatment for ALS; Violet and Amelia treat a woman with a brain tumor; Sheldon goes after Charlotte's affections.

Addison, Amelia and Fife try to save Maya and her unborn child; Sam makes a grim discovery; Cooper makes a valiant effort with Charlotte; an unexpected death leaves everyone stunned.