Thatcher Grey (Jeff Perry) returns to the hospital with stomach pains and a tattooed young girlfriend; Alex and ob-gyn Lucy Fields (Rachael Taylor) clash over a patient; and Mark puts Jackson on his service to get information from him about Lexie.
Derek breaks ground on his Alzheimer’s clinical trial and Meredith can’t help but feel left out; Bailey’s attempt to take the hospital into the age of new media with live tweets from the OR does not go over well with the Chief...