S7E3 - "Mars Attacks"

This week, a structural collapse at a sci-fi convention overwhelms the short-staffed ER, Abby and Luka share an intimate moment, Corday guides Mark through a delicate procedure, Frank tries to get some patients arrested, Malucci won't leave Chen alone, Benton has a huge surprise waiting for him at the hospital, and Carter's return to the ER isn't quite what he'd hoped for.