ELIZABETH HURLEY AND DESMOND HARRINGTON GUEST STAR – Chuck, Nate, Blair, Serena and Lola (guest star Ella Rae Peck) team up to uncover what they think is an explosive secret between Diana and Jack (guest star Desmond Harrington). Meanwhile, Dan is offered a prestigious fellowship in Rome for the summer. Matthew Settle also stars. Bart Wenrich directed the episode written by Jake Coburn.