Callie and Derek collaborate on a brain mapping project; Meredith thinks about continuing her mom's research; Shane's guilt persists.
When Nick inherits some money from his late father, Jess is determined to put the funds to good use by secretly tackling Nick's box of unwanted responsibilities, and his unpaid bills.
Buffy learns more about her sister Dawn when a menacing force finds its way to Sunnydale, and Buffy's mother falls ill for no apparent reason.
With Sorenson on restricted duties, Sipowicz is left to find evidence to convict Sidney of the subway knife attack.
