The residents compete for a solo surgery; Derek asks Bailey for advice when he feels Cristina is interfering in his relationship with Meredith; Erica discovers a surprising connection between a surgical resident and a longtime patient.
Richard tries to get Adele into Derek and Meredith's Alzheimer's trial; Arizona and Mark try to plan a baby shower for Callie; Henry has another medical complication; competition for the chief resident position is amplified.
A stampede at a comic book convention leads to an influx of colorful characters in the ER; Mark continues to make life difficult for Jackson; Ben returns and realizes Bailey has moved on.
Teddy is called away on another case, as Henry is brought in for emergency surgery; Derek and Meredith finally receive news about Zola; a patient experiences complications after surgery.
Owen and Cristina navigate their relationship amid the pending lawsuit; Bailey and Ben argue over wedding plans; while Jackson is distracted by a shocking situation with April, Callie asks him for help fixing Derek's hand.