Tom Connolly

The BAU investigates a group of suspects with a pack mentality who are randomly selecting their victims in the nation's capital and murdering them for the thrill of it.

Time shifts on the Island throw Sawyer, Juliet, Faraday, Locke and everyone else for a loop; Ben enlists Jack to get the Oceanic Six back together; Hurley enlists his parents' help when Sayid is tranquilized.

Desmond goes in search of a woman who could be the key to stopping the island's erratic movements through time. Meanwhile, Locke uncovers the identity of the hostile forces that have been attacking the remaining islanders.

When multiple American victims are found in Cuba, the team travels to the island in search of possible spree killers.

House's latest patient forces him to put his life under the proverbial microscope. Masters and Chase learn a few lessons too.

Veronica takes her private-investigator exam; Piz interviews a student who wrote a book about his years as an orphan child-soldier in Uganda's rebel army.