"Lockdown" is the 17th episode of the second season of the American drama television series Lost, and the 42nd episode overall. The episode was directed by Stephen Williams, and written by executive producers Carlton Cuse and Damon Lindelof. It first aired on ABC in the United States on March 29, 2006. "Lockdown" was seen by an estimated 16.21 million American household viewers. The episode received positive reviews from critics, with praise given for the plot development and Emerson's performance.